One of the best ways to keep in touch with us is to join our email list. You’ll receive a free copy of Our Top 12 Strategies for Long Term Success on A Raw Plant-Based Diet eBook along with regular information about raw food and plant-based diets and periodic promotions for our classes, events, and other offerings!
Beta-carotene absorption and conversion to vitamin A on a raw plant-based vegan diet
Where does one get vitamin A on a plant-based vegan diet?
Vitamin A is essential for proper cell growth and reproduction and is probably best known for its importance in vision. It also plays an important role in immune system function and skin health. Vitamin A (also known as retinol) is found exclusively in animal foods and various vitamin supplements. Vitamin A is an essential nutrient for humans, so if one is eating a vegan diet, where is this vitamin A obtained? Fortunately, the human body converts beta-carotene and certain other carotenoids to vitamin A when necessary. Beta-carotene is a well-known carotenoid famous for providing carrots with their orange coloring and is found in many other plant foods, especially green, yellow, and orange-colored fruits and vegetables.
Beta-carotene conversion to vitamin A
How does this conversion of beta-carotene to vitamin A work? In the human body, beta-carotene is converted to retinal by a dioxygenase enzyme. Retinal is then converted to retinol (vitamin A) by a dehydrogenase enzyme:
Other carotenoids that are capable of converting to vitamin A in the human body include alpha-carotene, gamma-carotene, and beta-cryptoxanthin. Of the four carotenoids, the one that converts the most reliably to vitamin A is beta-carotene.
Why is my skin orange?
Vitamin A is a fat-soluble nutrient, which means that it can be stored in our body and we run the risk of getting too much from outside sources, such as supplements consumed in excess of the body’s needs. Carotenoids are fat soluble also, but do not carry the same risks as vitamin A with excess consumption. In excess of the body’s needs, carotenoids are stored in fat cells including those under our skin, giving an orange color to the skin which is only cosmetic.
Do we have to cook our food to get enough beta-carotene and vitamin A?
Many people have asked about the effectiveness of this carotenoid conversion mechanism and how well carotenoids are absorbed from raw food. A recent study found normal vitamin A status and favorable blood beta-carotene levels in 200 long-term raw food enthusiasts. This indicates is that these raw foodists consumed a good amount of beta-carotene, a quantity was absorbed and was present in their bloodstream, and then an appropriate amount was converted into vitamin A.
References:
Fleshman, Matthew Kintz. Beta Carotene Absorption and Metabolism. Ph.D. dissertation, Ohio State University, 2011.
Garcia A, Koebnick C, Dagnelie P, Strassner C, Elmadfa I, Katz N, Leitzmann C, Hoffman I. British Journal of Nutrition 2008; 99: 1293 – 1300.
Interested in taking your vitamin A, beta-carotene, and general nutrition knowledge to the next level?
We cover this topic and so much more in our online Mastering Raw Food Nutrition and Educator Course. For more class details, click here.
Additionally, our book The Raw Food Nutrition Handbook: An Essential Guide to Understanding Raw Food Diets addresses many hot topics in raw food nutrition such as essential fats, protein, nutrient content of raw food diets, food combining, enzymes, hydration, vitamins, minerals, and many more. We value education on these important topics and are happy to finally bring this book to you. The book is available on Amazon and other online booksellers.
One of the best ways to keep in touch with us is to join our email list. You’ll receive a free copy of Our Top 12 Strategies for Long Term Success on A Raw Plant-Based Diet eBook along with regular information about raw food and plant-based diets and periodic promotions for our classes, events, and other offerings!
Enhance Your Raw Food Diet with Home Grown Produce!
Spring is in the air and gardening season has begun in our home! Some of the many joys a raw food enthusiast experiences in Springtime are: preparing soil in raised beds to grow favorite garden vegetables, choosing the perfect vegetable starts, then planting them and watching them grow throughout the season. Harvest time is always exciting, too, as we reap the “fruits of our labor” (and the vegetables, too!).
Plant leafy greens for optimal nutrition
This year, in order to pack our raw vegan diet with optimal nutrition, we’ve planted a plenitude of leafy greens, including several types of lettuce, frisée (curly endive), dandelion greens, arugula, two types of kale, and two types of collard greens. The lettuce varieties we planted are heirloom varieties of green leaf, red leaf, red Romaine, green Romaine, and red oak leaf. Lettuce, frisée, and dandelion greens are all members of the sunflower family (Asteraceae), while arugula, kale, and collard greens are members of the cabbage family (Brassicaceae). Members of this plant family are also known as cruciferous vegetables, and include broccoli, cauliflower, maca, turnip, rutabaga, Brussels sprouts, watercress, red and green cabbage, bok choy, and Napa cabbage.
We’ve also planted several varieties of tomatoes, including some of the heirloom varieties we love, like Pineapple tomatoes, Cherokee Purple, Green Zebra, Brandywine, and several different types of cherry tomatoes. Several tomato varieties love heat, and we planted those in our yard on the south side of the house, which is warmer than the rest of our yard and more sheltered from the wind. Tomatoes are part of the nightshade family (Solanaceae) along with bell peppers, eggplant, potatoes, tomatillos, goji berries, Incan berries, jalapeño peppers, and other hot pepper varieties.
Plant mints in containers for best results
We have quite a few plants from the mint family in our yard this year, including several types of basil and four types of mint. Mints have a tendency to grow and spread prolifically. Early in my gardening career I made the mistake of planting mint in my raised beds and found out the hard way that mint plants have a tendency to “take over” the garden. This year, I learned from past experience and planted the mints in half wine barrels to keep them appropriately contained. However, if you want a very aromatic ground cover, Corsican Mint is a beautiful choice. A couple of years ago, I planted it in a makeshift herb garden in a non-grassy area of my yard. It has since spread and creates a deliciously fragrant chocolate mint addition to the area. It may surprise you to know that Chia seeds are another member of the mint family famously popular in the raw food community!
On the other hand, most types of basil stay localized in their growth habit, so I plant basil directly in my raised beds. They make a lovely companion planting next to the tomatoes, and the two are a perfect culinary combination, especially in Italian cuisine.
Fruit-bearing plants in our yard include two types of lemon trees and a fig tree, which is already producing numerous small figs. The fig tree is only five years old, and has already been producing numerous baskets of figs for the last three seasons. Since we adore figs, we’re really looking forward to harvest time later this year!
Plant fruits and vegetables no matter where you live
This is a small sampling of the foods we are currently growing in our yard and garden. We enjoy being able to create more diversity in our raw food diets and growing foods we enjoy that can be harder to find in the grocery store aisles. Even more importantly, we notice a big difference in the taste and quality of the foods we grow compared to the ones we buy. We suggest growing fruits and vegetables—you’ll be well rewarded in both taste and nutritional value. Before we had a back yard, we grew vegetables and fruits on our apartment patio, and sprouts, greens, and grasses near a window in our dining room. There are so many ways to grow your own food, and at harvest time, you’ll be grateful that you made the worthwhile effort. Happy gardening!
One of the best ways to keep in touch with us is to join our email list. You’ll receive a free copy of Our Top 12 Strategies for Long Term Success on A Raw Plant-Based Diet eBook along with regular information about raw food and plant-based diets and periodic promotions for our classes, events, and other offerings!
Raw Food and Prebiotics for Health
There has been a lot of talk about the importance of probiotics for health in the media recently. As a result, there are now numerous products on the market that are supplemented with probiotics. It’s important to understand not only the health benefits of probiotics, but how to keep them alive once they are in the intestinal tract.
Probiotics need food to survive, and once in our intestinal tract, probiotics can stay alive on the foods we ingest. Just like people, probiotics thrive on specific types of foods, especially certain types of fiber. Fiber is not digestible by humans, but is fermentable by probiotics. Fiber that can provide food for probiotics is referred to as a prebiotic. Most types of fiber are composed of glucose molecules hooked together by chemical bonds; but the types of fiber that probiotics prefer as a source of food are composed of fructose molecules hooked together by chemical bonds. These types of fiber include fructooligosaccharides (FOS) and inulin.
Probiotics break down fructooligosaccharides and inulin into fructose and free fatty acids. The resulting fructose is then used as a food source by the probiotics and the free fatty acids serve as a food source for the cells that line our large intestine. In this way, among many others, probiotics help to provide food for us.
Raw Food Plant Based Diet Rich Source of Prebiotics
Inulin and fructooligosaccharides occur naturally in greater than 36,000 plant species in varying amounts. Some of the richest sources of inulin and FOS include banana, dandelion greens, garlic, artichoke, Jerusalem artichoke, onion, leek, yacon, shallot, and many more. There are numerous other commonly consumed raw foods that provide smaller amounts of these types of fiber, including lettuce, snap peas, snow peas, carrots, peaches, blackberries, watermelon, navel oranges, black grapes, raspberries, other fruits and vegetables, and some whole grains. Fruits and vegetables provide plenty of this and many other beneficial types of fiber, which is just one of a myriad of benefits derived by consuming large quantities of fruits and vegetables in one’s daily diet.
There is still much to learn about the health benefits and preferred foods of probiotics, and the media buzz on probiotics continues to grow. There have been articles in major newspapers including the New York Times on the possible connection between probiotics and maintaining a healthy weight, attributed to the ability of probiotics to use calories from our food for their own energy needs. This way, those extra calorie sources are consumed by probiotics rather than being absorbed by the body and stored as fat.
This is just the tip of the iceberg! We include much more information about the importance of probiotics and prebiotics in our Mastering of Raw Food Nutrition. We’d love for you to join us to learn more about this and many other fascinating topics on the science of plant based raw food nutrition.
References and Research:
Bosscher D(1), Breynaert A, Pieters L, Hermans N. Food-based strategies to modulate the composition of the intestinal microbiota and their associated health effects. J Physiol Pharmacol. 2009 Dec;60 Suppl 6:5-11.
de Vrese M(1), Schrezenmeir J. Probiotics, prebiotics, and synbiotics. Adv Biochem Eng Biotechnol. 2008;111:1-66.
Kechagia M(1), Basoulis D(2), Konstantopoulou S(1), Dimitriadi D(1), Gyftopoulou K(1), Skarmoutsou N(1), Fakiri EM(1). Health benefits of probiotics: a review. ISRN Nutr. 2013 Jan 2;2013:481651.
Kelly G. Inulin-type prebiotics--a review: part 1. Altern Med Rev. 2008 Dec;13(4):315-29.
Niness K. Inulin and oligofructose: what are they? J Nutr 1999; 129 (7 Suppl): 1402S – 1406S.
Quigley EM. Prebiotics and probiotics; modifying and mining the microbiota. Pharmacol Res. 2010 Mar;61(3):213-8.
Roberfroid M(1), Gibson GR, Hoyles L, McCartney AL, Rastall R, Rowland I, Wolvers D, Watzl B, Szajewska H, Stahl B, Guarner F, Respondek F, Whelan K, Coxam V, Davicco MJ, Léotoing L, Wittrant Y, Delzenne NM, Cani PD, Neyrinck AM, Meheust A. Prebiotic effects: metabolic and health benefits. Br J Nutr. 2010 Aug;104 Suppl 2:S1-63.
Slavin J. Fiber and prebiotics: mechanisms and health benefits. Nutrients. 2013;5:1417-1435.
Thomas LV(1), Ockhuizen T(2), Suzuki K(3). Exploring the influence of the gut microbiota and probiotics on health: a symposium report. Br J Nutr. 2014 Jul;112 Suppl 1:S1-S18.
One of the best ways to keep in touch with us is to join our email list. You’ll receive a free copy of Our Top 12 Strategies for Long Term Success on A Raw Plant-Based Diet eBook along with regular information about raw food and plant-based diets and periodic promotions for our classes, events, and other offerings!
The Calcium Content of Fruit
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Is Lettuce a Superfood?
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Video on the Vitamin E content in Raw and Roasted Almonds
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Why is fruit easier to digest than other foods?
In this article and video we will explore why fruit can be easier to digest than other foods by understanding several aspects of digestive physiology.
There are three macronutrients that we find in whole foods: carbohydrate, protein, and fat. Fruit is high in carbohydrate and in general, carbohydrates tend to be more quickly digested than protein and fat.
Here is a chart that illustrates the carbohydrate, protein, and fat content (as a percentage of calories) of various types of foods:
| Type of Food | Carbohydrate | Protein | Fat |
| Fruit | 89% | 6% | 5% |
| Vegetables | 73% | 18% | 9% |
| Nuts and Seeds | 16% | 11% | 73% |
| Legumes | 66% | 30% | 4% |
| Grains | 80% | 12% | 8% |
| Oil | 0 | 0 | 100% |
| Avocados | 19% | 5% | 76% |
| Coconuts | 17% | 4% | 79% |
| Spirulina | 26% | 64% | 10% |
As we can see, the macronutrient content of fruit averages 89% carbohydrate, 6% protein, and 5% fat. Fruit is the highest in carbohydrate of the food groups listed.
Types of carbohydrates
There are three different types of carbohydrates: polysaccharides, disaccharides, and monosaccharides. Monosaccharides are composed of a single sugar, as the name would imply. Mono means “one” and saccharide means “sugar”. Disaccharides are two monosaccharides hooked together by a chemical bond. Polysaccharides are composed of multiple monosaccharides hooked together by chemical bonds. For further clarification, there are two types of polysaccharides, digestible and non-digestible. An example of a digestible polysaccharide is starch and a non-digestible example is fiber. Starch is also referred to as “complex carbohydrate”, while fiber is also known as “cellulose”.
Complex carbohydrates, such as starch, and disaccharides have chemical bonds that must be broken down by digestive enzymes into monosaccharides in order to be absorbed. The human body uses the carbohydrate-digesting enzyme amylase to break down complex carbohydrates into simpler carbohydrates. A common disaccharide is sucrose, which is composed of glucose and fructose hooked together by a chemical bond. Since sucrose is a disaccharide, it is broken down by the digestive enzyme sucrase into the monosaccharides glucose and fructose, which can then be absorbed.
To summarize, monosaccharides are absorbed by our digestive tract, so carbohydrates that are more complex must be broken down into monosaccharides in order to be absorbed.
Carbohydrates in fruit
The carbohydrates found in fruit are primarily fructose and glucose, both of which are monosaccharides, so they do not need to be broken down further by digestive enzymes. This is a reason why fruits are often referred to as being “predigested”. In other words, our body absorbs fructose and glucose “as is”, without using digestive enzymes to break them down further.
Here is a chart showing the fructose, glucose, sucrose, and complex carbohydrate content of various fruits:
| Food | Fructose (g) | Glucose (g) | Sucrose (g) | Complex carbohydrate (g) |
| Mango – one whole (207 g) | 6.00 | 1.45 | 20.5 | 0.83 |
| Blueberries – one cup (148 g) | 7.36 | 7.22 | 0.16 | 3.15 |
| Cantaloupe – 3lbs. (1360 g) | 23.69 | 19.47 | 55.10 | 0.17 |
| Apricots – one cup sliced (165 g) | 1.54 | 3.87 | 9.58 | 0.0 |
| Figs – 5 dried | 9.63 | 10.41 | 0.03 | 2.0 |
| Raspberries – 1 cup (123 g) | 2.89 | 2.29 | 0.25 | 1.25 |
| Strawberries – 1 cup sliced (166 g) | 4.04 | 3.30 | 0.78 | 1.31 |
| Apples – one medium (182 g) | 10.72 | 4.42 | 3.76 | 1.86 |
| Watermelon – One cup diced (152 g) | 5.09 | 2.40 | 1.84 | 1.44 |
| Grapes – One cup red (151 g) | 12.28 | 10.87 | 0.23 | 2.60 |
| Pineapple – One cup chunks (165 g) | 3.50 | 2.85 | 9.88 | 3.09 |
| Banana – one medium (118 g) | 5.72 | 5.88 | 2.82 | 6.35 |
The fructose and glucose content of these fruits is notable, especially when compared to the complex carbohydrate content, which is in several cases quite a bit lower. The sucrose content of these fruits varies by type of fruit.
This next chart shows the carbohydrate content of other various other plant foods:
| Food | Fructose (g) | Glucose (g) | Sucrose (g) | Complex carbohydrate (g) |
| Bell pepper – 1 cup chopped red (149 g) | 3.22 | 2.77 | 0 | 2.99 |
| Tomatoes – One cup chopped (180 g) | 2.47 | 2.25 | 0 | 2.34 |
| Carrots – One cup chopped (110 g) | 0.60 | 0.65 | 3.95 | 2.24 |
| Lettuce – 4 cups shredded (188 g) | 1.50 | 0.73 | 0 | 3.96 |
| Yam – One whole (130 g) | 0.91 | 1.25 | 3.28 | 16.28 |
| Lentils – ½ cup (96 g) | 0.26 | 0.0 | 1.40 | 26.45 |
| Brown rice – med grain, ½ cup (95 g) | 0 | 0 | 0 | 74.82 |
The yam, lentils, and brown rice on this table contain much more complex carbohydrate than the fruits we examined in the previous table. These foods are also generally much lower in glucose, fructose, and sucrose than the fruits. This would suggest that yams, lentils, brown rice and other foods high in complex carbohydrates would require more digestive enzyme activity than fruits, which contain simpler carbohydrates. Vegetables, such as carrots and lettuce, are in a less extreme but similar category since they contain fewer simple carbohydrates and generally more complex carbohydrates than most fruits.
In summary, the higher simple carbohydrate content, lower complex carbohydrate content, and lower protein and fat content of fruit versus other foods may account for the reason why the digestion of fruit requires less digestive enzyme activity than other foods. This ease of digestion and simple carbohydrate content constitute at least part of the reason why fruit can provide us with quick energy for our daily activities, and perhaps even our natural detoxification and healing processes. I look forward to a time when more information is available to share with you on this fascinating topic!
Isn’t fruit controversial for some reason?
To make it easy for people to find reliable information on fruit, the glycemic index, glycemic load, fructose, glucose, and carbohydrates in general, we dedicated a chapter in our book, The Raw Food Nutrition Handbook: An Essential Guide to Understanding Raw Food Diets to answering many common carbohydrate questions.
In the book we also cover other hot topics in raw food nutrition such as essential fats, protein, nutrient content of raw food diets, food combining, enzymes, hydration, vitamins, minerals, and many more. We value education on these important topics and are happy to finally bring this book to you. The book is available on Amazon and other online booksellers.
One of the best ways to keep in touch with us is to join our email list. You’ll receive a free copy of Our Top 12 Strategies for Long Term Success on A Raw Plant-Based Diet eBook along with regular information about raw food and plant-based diets and periodic promotions for our classes, events, and other offerings!
Does our body release all types of digestive enzymes at the same time?
This is a great question that is often asked in the context of food combining. Much of the information disseminated about food combining in the raw food community is decades-old, so here I will cover this topic from the perspective of current digestive physiology. Our body makes three main types of digestive enzymes: amylase for carbohydrate digestion, proteases for protein digestion, and lipase for fat digestion.
Depending where we are in the digestive system, our body will release certain types of digestive enzymes. For example, when we are chewing food, our salivary glands release saliva along with two types of digestive enzymes: salivary amylase for carbohydrate digestion and lingual lipase for fat digestion, so carbohydrate and fat digestion begin in the mouth. After food has been chewed, it is swallowed and moves down the esophagus into the stomach. There, the food comes in contact with other digestive factors such as hydrochloric acid and a protein digesting enzyme called pepsin, so protein digestion begins in the stomach.
After food leaves the stomach, it moves into the small intestine, where it interacts with digestive factors secreted by the pancreas. These factors include the enzymes amylase, protease, and lipase for carbohydrate, protein, and fat digestion, respectively. The pancreas releases ALL THREE types of these enzymes at the same time. This fact is important, given that the foods that we eat are some combination of carbohydrate, protein, and fat. One notable exception is oil with 100% of the calories from fat.
Here are some plant foods and their carbohydrate, protein, and fat content as a percentage of calories:
| Type of Food | Carbohydrate | Protein | Fat |
| Fruit | 89% | 6% | 5% |
| Vegetables | 73% | 18% | 9% |
| Nuts and Seeds | 16% | 11% | 73% |
| Legumes | 66% | 30% | 4% |
| Grains | 80% | 12% | 8% |
| Oil | 0 | 0 | 100% |
| Avocados | 19% | 5% | 76% |
| Coconuts | 17% | 4% | 79% |
| Spirulina | 26% | 64% | 10% |
As you can see, all of these foods contain some amount of each of the three macronutrients. We think of fruits as being a high in carbohydrates, but they also contain some protein and fat! Occasionally, I hear people say that nuts and seeds are a rich source of protein, but in reality, they are much higher in fat. Per calorie, vegetables are a more notable source of protein than nuts and seeds.
Our take home message here is that all whole foods are some combination of carbohydrate, protein, and fat so it is important that the body release enzymes for digestion of all three of these macronutrients at the same time. Additionally, these enzymes do not cancel each other out as some food combining literature states. As mentioned earlier, there is much that we have learned about digestive physiology since food combining principles were first introduced years ago, and we will certainly learn more in years to come. This does not mean that we should disregard food combining principles altogether, but instead use the individual principles that best support our personal health.
Here is video summarizing this information:
For those of you interested in learning more about food combining from the perspective of current research and digestive physiology, my book, the Raw Food Nutrition Handbook: An Essential Guide to Understanding Raw Food Diets provides this information using easy to understand language. I cover this topic and many more hot topics in raw food and nutrition in general to support you in your health journey.
One of the best ways to keep in touch with us is to join our email list. You’ll receive a free copy of Our Top 12 Strategies for Long Term Success on A Raw Plant-Based Diet eBook along with regular information about raw food and plant-based diets and periodic promotions for our classes, events, and other offerings!
Video: What I Learned about Vitamin B12 from the Framingham Offspring Study
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Video on the Selenium Content of Brazil Nuts
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Three common vitamin D questions answered: Is vitamin D deficiency just for vegans, how is vitamin D made in our skin, and what is the best test for vitamin D?
Is vitamin D deficiency just for vegans?
Many times I have heard people say that they stopped eating a plant-based vegan diet because they tested low in vitamin D. The fact is that vitamin D deficiency is not solely an issue for vegans, vegetarians, and raw foodists. A 2011 study estimated the prevalence of vitamin D deficiency in the US population at 42 percent on average and in some segments of the population this prevalence is as high as 82 percent. The researchers in this study defined vitamin D deficiency as a blood level of vitamin D less than or equal to 20 ng/ml. Opinions on this number differ. For example, various clinicians and the Vitamin D Council define vitamin D deficiency as less than or equal to 30 ng/ml, so these sources may see the estimated average vitamin D deficiency prevalence in the US as higher than 42%.
According to a Vegetarian Times survey, about 3% of the US population follows a vegetarian diet and approximately half of these people identify as vegan. As we can see from the stats mentioned above, vitamin D deficiency is clearly not just a concern for vegans, vegetarians, and raw food enthusiasts. Vitamin D status is an important consideration for everyone regardless of diet.
How is vitamin D made in our skin?
When we are outside and we have bare skin exposed to the sun, ultraviolet B spectrum rays interact with 7-dehydrocholesterol in our skin to produce cholecalciferol, also known as vitamin D3. After vitamin D3 is formed, it travels via the bloodstream down to the liver where it is converted to 25-hydroxycholecalciferol, also known as 25-hydroxyvitamin D3. 25-hydroxycholecalciferol then travels via the bloodstream down to the kidneys, where it is transformed to 1,25-dihydroxycholecalciferol, also known as 1,25-dihydroxyvitamin D3, which is considered to be the activated form of vitamin D.
Vitamin D3 is produced in an area of the skin called the epidermis. The epidermis has five layers, the first of which we can see, called the stratum corneum. Vitamin D3 is produced further down in levels 4 and 5 of the epidermis called the stratum spinosum and the stratum basale, after which vitamin D3 travels through the bloodstream to the liver for conversion.
Many people spend time in the sun but still find that they test low in vitamin D. There are some factors that can inhibit vitamin D production in the skin, specifically air pollution, skin type, time of day, age, sunscreen usage, latitude, time of year, and other factors. For example, air pollution in significant amounts can potentially obscure the rays of the sun, inhibiting skin production of vitamin D.
Sunscreen use at SPF 8 and above may affect the production of vitamin D in the skin as can latitude and season. For example, the ability of one’s skin to make vitamin D year round is consistent at 35 degrees north latitude and below in the northern hemisphere*, or 35 degrees south latitude and above in the southern hemisphere*. In the United States, 35 degrees north is Los Angeles on the west coast and the border of North and South Carolina on the east coast. The ability of one’s skin to make vitamin D in the winter will be reduced or eliminated for someone living above 35 degrees north and below 35 degrees south. Simply stated, people who live in northern parts of the United States have been found not to produce vitamin D in their skin during the winter months.
How do we determine our vitamin D status?
The best way to know is to get a blood test, and the test currently considered to be the best measurement of vitamin D status is known as the 25-hydroxycholecalciferol, 25-hydroxyvitamin D3, or 25-OH D3 test.
Would you like to learn how much vitamin D is made in the skin per unit time or are you interested in taking your general vitamin D and nutrition knowledge to the next level? We cover this topic and so much more in our online Mastering Raw Food Nutrition and Educator Course. Mastering Raw Food Nutrition is the updated and expanded version of our popular Science of Raw Food Nutrition classes. For more class details, click here.
Additionally, our book The Raw Food Nutrition Handbook: An Essential Guide to Understanding Raw Food Diets addresses many hot topics in raw food nutrition such as vitamin D, essential fats, protein, nutrient content of raw food diets, food combining, enzymes, hydration, vitamins, minerals, and many more. We value education on these important topics and are happy to finally bring this book to you. The book is available on Amazon and other online booksellers.
One of the best ways to keep in touch with us is to join our email list. You’ll receive a free copy of Our Top 12 Strategies for Long Term Success on A Raw Plant-Based Diet eBook along with regular information about raw food and plant-based diets and periodic promotions for our classes, events, and other offerings!
References:
Dina K, Dina R. The Raw Food Nutrition Handbook. Summertown, TN: Healthy Living Publications, 2015.
Forrest KY, Stuhldreher WL. Prevalence and correlates of vitamin D deficiency in US adults. Nutr Res. 2011 Jan;31(1):48-54.
http://www.vegetariantimes.com/article/vegetarianism-in-america/
www.vitamindcouncil.org
*Examples of areas in the northern hemisphere include North America, Europe, and Asia. Examples of areas primarily in the southern hemisphere include: South America, Australia, New Zealand, and islands of the South Pacific Ocean. Africa is located in both the northern and southern hemispheres.
Here is a video summarizing this information on how vitamin D is made in the skin:
Video for My Pomegranate Green Smoothie Recipe
Here is the recipe:
½ cup of fresh pressed pomegranate juice
1 cup fresh pressed Valencia orange juice
2 medium bananas, peels removed
3 cups chopped kale, loosely packed
1 cup chopped mangoes, peels removed
½ cup blueberries
½ cup blackberries
Here is a nutrient analysis of the ingredients in this smoothie:
| Adult Daily Values | ||
| Protein | 15 grams | |
| Calcium | 361 | 1000 – 1200 mg |
| Iron | 5.7 | 8 – 18 mg |
| Zinc | 2.2 | 8 – 11 mg |
| Magnesium | 203 | 310 – 420 mg |
| Potassium | 2876 | 4700 mg |
| Vitamin C | 462 | 75 – 90 mg |
| Vitamin E | 4.0 | 15 mg |
| Vitamin B1 | 0.7 | 1.1 – 1.2 mg |
| Vitamin B2 | 0.7 | 1.1 – 1.3 mg |
| Vitamin B3 | 6.6 | 14 – 16 mg |
| Vitamin B5 | 2.3 | 5 mg |
| Vitamin B6 | 1.9 | 1.3 – 1.7 mg |
| Folate | 258 | 400 mcg |
| Beta carotene | 19538 mcg |
This is one of my post-workout green smoothies. On days that I do not have a big workout, my smoothies are usually smaller.
One of the best ways to keep in touch with us is to join our email list. You’ll receive a free copy of Our Top 12 Strategies for Long Term Success on A Raw Plant-Based Diet eBook along with regular information about raw food and plant-based diets and periodic promotions for our classes, events, and other offerings!
Video on Jerusalem artichokes: nutrient content, gardening experience, and an easy recipe
One of the best ways to keep in touch with us is to join our email list. You’ll receive a free copy of Our Top 12 Strategies for Long Term Success on A Raw Plant-Based Diet eBook along with regular information about raw food and plant-based diets and periodic promotions for our classes, events, and other offerings!
Video for My Simple Green Juice Recipe
I have shared this recipe on my blog in the past and now I have a short video explaining how I make this juice:
This juice has been one of my favorites for years because of its simplicity, nutrient content, and versatility. I find it to be a great introductory juice recipe for people new to juicing, since it has a lighter taste than green juice that contains darker leafy greens. I personally love the taste of dark leafy greens, but for some, the taste may need some “getting used to”. I can certainly appreciate this, given that when I became interested in health years ago, I did not even know that dandelion greens were edible. Now, they are one of my favorite leafy greens!
Here is the recipe:
5 stalks of celery (12” long)
1 lemon, peeled
2 medium cucumber, 8” long
This recipe makes about 32 ounces of juice. Here are some of the nutrients found in these ingredients:
| Light Green Juice ingredients | Adult Daily Values | |
| Calories | 165.9 | |
| Calcium | 246.2 | 1000 – 1200 mg |
| Iron | 2.83 | 8 – 18 mg |
| Zinc | 1.67 | 8 – 11 mg |
| Magnesium | 120.2 | 310 – 420 mg |
| Potassium | 1832.9 | 4700 mg |
The mineral content of such simple ingredients is amazing to me, especially calcium and iron. The sodium content of these ingredients is 270 mg, most of which is found in the celery. Cheers!
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My Top 5 Favorite Leafy Greens
1. Lettuce
From the beginning of my raw food journey in 1990, lettuce has been one of my go-to leafy greens. I love the mild taste and versatility of lettuce, which often forms the basis for my salad recipes. Before my interest in raw food developed, I knew of one type of lettuce: iceberg. This changed quickly as I learned of the many varied types of lettuce including grocery store mainstays such as Romaine, green leaf, red leaf, and Boston. When I started shopping at farmers markets and growing my own food several years ago, I became familiar with lesser known and heirloom varieties of lettuce that expanded my lettuce repertoire further. Right now, Rick and I have 8 varieties of lettuce growing in our backyard garden. Lettuce is a member of the sunflower plant family.
2. Dandelion Greens
Dandelion greens are popularly consumed as an early spring green, but I personally love dandelion greens year round, and enjoy them in my salads, smoothies, and juices. The mineral content of dandelion greens is notable and rivals kale in calcium content. Dandelion greens are in the sunflower plant family (Asteraceae), along with lettuce, endive, escarole, frisée greens, sunflower seeds, and Jerusalem artichokes.
3. Tree Collard Greens
Rick and I planted several collard plants in our garden when moved into our house a few years ago, and they are still going strong and producing beautiful large deep green leaves, year round in northern California. What we love about our tree collards is that they are relatively low maintenance and are a reliable source of greens for us. We enjoy greens from our tree collard plants mostly in smoothies, but occasionally put them in juice or a salad. These tree collard greens are tender and easily digestible for us in comparison to collard greens we find in the grocery store that generally have a tougher consistency. Our tree collards are now about 12 feet tall and still growing, with numerous leaves that can measure up to 8 inches in diameter or more. Collard greens, like other members of the cabbage family (Brassicaceae) contain noteworthy amounts of certain minerals.
4. Kale
Kale is most certainly one of our many favorite leafy greens and a backyard garden staple. I first became interested in kale when I discovered its impressive calcium and iron content, which is not surprising, given that kale is a member of the cabbage family. Members of the cabbage plant family are also called “cruciferous”, in reference to the cross-like appearance of their flowers, or “brassica” vegetables, reflecting their plant family name Brassicaceae. Rick and I enjoy kale in smoothies, juices, soups, and many other recipes. Since we like to have a variety of foods in our diet, we rotate our leafy greens to enjoy the diversity of flavors, textures, and nutrients offered by different leafy greens. For example, we might have kale as our main leafy green on one day, dandelion greens the next, frisée greens the next, and so forth.
5. Escarole
Rick and I recently returned home from traveling, visiting, and teaching on the east coast to find that the tiny escarole starts we planted in September had grown into huge plants, with 9-inch diameter leaves, at the largest. Given the size of the leaves, this escarole would make great wraps. We have found that escarole grows well in cooler weather, so the size of our plants is not a surprise, given that it is mid-November.
Escarole is in the sunflower plant family, so its strong resemblance to some lettuce varieties is justified. I have found that the taste of escarole can vary, for example, the escarole growing in our yard has a more mild taste than the more bitter versions I have found in grocery stores and farmers markets.
Here are some of the nutrient highlights of escarole:
| 3 cups chopped escarole (150 g) | Adult Daily Values | |
| Calories | 25.5 | |
| Calcium | 78 mg | 1000 – 1200 mg |
| Iron | 1.24 mg | 8 – 18 mg |
| Zinc | 1.18 mg | 8 – 11 mg |
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Collard Greens and Tree Collard Greens
April 1st is upon us and here in northern California, Rick and I have been preparing our backyard raised beds for planting. This year, we are planting many of our garden staples such as heirloom tomatoes, squash, bell peppers, basil, and some plants we have not grown before, such as mizuna and stinging nettle. One plant that grows year round in our garden is tree collard greens. We have several tree collard plants that have been in our garden since we moved into our house a few years ago, and they are still going strong and producing beautiful large deep green leaves.
What we love about our tree collards is that they are relatively low maintenance and are a reliable source of greens for us. Of course, we rotate our greens for variety so we are planting a variety of other greens in our garden this year, which we will cover in another blog post or video. We enjoy greens from our tree collard plants mostly in smoothies, but occasionally may put them in juice or a salad. These collard greens are tender and easily digestible for us in comparison to collard greens we find in the store that have a tougher consistency. We have observed over the years, that the greens that we grow in our garden tend to be softer and more tender than commercially available greens. Although this may not be true across the board, this is just an observation from our own personal experience.
Here is a sampling of the nutrients found in regular collard greens:
| 3 cups chopped collard greens (108 g) | Adult Daily Values | |
| Calories | 32.4 | |
| Calcium | 156.60 | 1000 – 1200 mg |
| Potassium | 182.52 | 4700 mg |
| Folate | 179.28 | 400 mcg |
| Beta carotene | 4149.36 mcg |
How do these numbers compare to the nutrients found in actual tree collard greens? We have yet to know, given that I have not yet been able to find neutral information on the nutrients measured in actual tree collard leaves. I would not be surprised if they are similar. This is the beauty of science and research, there is much that is known and much that has yet to be known. Happy spring!
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Why We Love Our Local Farmers Markets
One of the many questions that Rick and I are asked about raw food is where to find it at reasonable prices. In my last blog post, I wrote about wholesale produce markets, which can really help one save money when produce is purchased in quantity, providing that one has access to a wholesale produce market. What about areas where one does not have access to such a place? One alternative is a local farmers market.
We love farmers markets. They are a great place find locally grown produce and to interact with the farmers directly, if they are present to sell their produce personally – and many of them do so. Numerous times I have asked the farmers about their food producing techniques, an opportunity that I find to be very valuable. For me, this is a great way to have knowledge of how our food is produced and how it is handled. I have also found the food to be exceptionally fresh! An average head of lettuce purchased at our local farmers market lasts about 2 weeks before showing signs of withering. Produce that I buy at our local farmers market is often picked the same day that I buy it – how much more fresh can one get! Given that our diets are based on fresh produce, Rick and I buy in large quantities, and many of the farmers often give us a price break on the food we buy. Several of the farmers from whom we buy know us by name and actually anticipate our arrival at the market, by putting aside the usual foods that we buy from them. Talk about personal service – we really enjoy having a personal connection with the people from whom we buy food!
Since we live in northern California, our local farmers markets are open year round. In other areas, we have noticed that farmers markets depend on the local growing season and produce availability. Similarly, the variety of produce at our local farmers market depends on the type of food being grown locally at the time. For example, winter is a great time to find oranges, fall and early winter is the best time to find locally grown almonds, and of course summer is the most abundant season of all! Here, Rick and I can get lettuce and other green leafy vegetables at our farmers market year round, along with a variety of other fruits and vegetables. Such availability makes eating a produce-based diet much simpler.
It is wonderful to see that farmers markets appear to have gained popularity in the last 5+ years, especially in areas that did not have such markets several years ago. It is great to see that the trend of eating more locally grown food and supporting local farmers directly is continuing to grow. I hope that one day this is no longer a trend, but a mainstay in our communities.
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Saving money with wholesale produce
Our new YouTube channel is LIVE! After so many requests, we finally have a YouTube channel where we will be posting videos on a variety of health related topics! We have a couple of videos posted there now, including Rick’s three part essential fat video, and a video about our visit to the NY wholesale produce market:
Rick and I have visited wholesale markets in both the San Francisco bay area and the New York metro area. We live in the SF bay area, so when we buy from our local wholesale produce markets we buy enough food to last us about 3 weeks. Why so much? The food available at wholesale markets is sold in boxes or cases. This works well for us because the produce is so fresh, that it lasts for often weeks at a time in our large-capacity dedicated refrigerator.
We have found that when we buy lettuce at wholesale, the heads are very large, since very few, if any of the outer leaves have been removed. These heads of lettuce are generally larger than the heads we see at the grocery store, which likely have had leaves removed to maintain a fresh look. I really enjoy going to wholesale markets because of the wide variety of food available, especially organic. A very large percentage of the food that we eat is organically grown here in California.
For produce enthusiasts like us, wholesale markets can be a great way to purchase in quantity and save a notable amount of money. Rick has calculated that on average, we spend about 50% less money on produce from the wholesale markets that we would spend on the same amount of produce at the grocery store. You may be wondering if we go to farmers markets and the answer is yes, we love our local farmers market! We can often find foods at the farmers market that are not available at the wholesale market and vice versa.
The wholesale markets we have attended open around midnight or later and close around 10 am or earlier, depending on the vendor, so Rick and I find ourselves waking at 5 am to beat rush hour to the markets. I especially love these markets, since our need to go shopping for food weekly is drastically reduced. I find myself only having to do some minor fill-in shopping for items not available at the wholesale markets, maybe once a week or twice a month. With this shopping strategy, Rick and I overall spend much less time shopping and have more time available for work and other activities we enjoy.
The challenge is that our local wholesale markets are in San Francisco and South San Francisco which are about an hour and fifteen minutes away from our home if there is little traffic. The wholesale produce market that we have visited in the New York area is in the Bronx, which is also about an hour and fifteen minutes from our parents’ homes, where we stay on our visits to the New York metro area. This market has similar hours to our bay area wholesale markets, but is much larger.
Without a doubt, wholesale markets are certainly an experience and a great way to buy fresh produce in quantity. They can also be a tremendous resource for people who live in areas that have limited access to fresh produce year round, providing that the person lives within driving distance of a wholesale market. Many major metro areas have wholesale markets, and our experience at the two we have visited is that most vendors sell to individuals, although some sell exclusively businesses. You will have to check with individual vendors to learn their sales policies.
One of the best ways to keep in touch with us is to join our email list. You’ll receive a free copy of Our Top 12 Strategies for Long Term Success on A Raw Plant-Based Diet eBook along with regular information about raw food and plant-based diets and periodic promotions for our classes, events, and other offerings!