The new buzz word is Vegan. It’s practically everywhere you go and everywhere you look right now from social media posts, best-selling books, athletes to perfectly sculpted bodybuilders. It’s being endorsed everywhere, in fact, it’s pretty much impossible to get through the day without hearing the word “VEGAN”!
Yes, a Vegan diet is, in theory, healthy, after all its plant-based nutrition. So why then are several Vegans coming to me with signs of nutrient deficiencies, imbalanced gut bacteria, lack of energy and even excessive weight gain?
It’s because considerable care must be taken when choosing to be Vegan. It should include an appropriate knowledge of what makes up a nutritionally adequate diet and it shouldn’t be influenced by any media hype!
BEING VEGAN
A Vegan diet is by definition a diet that has no animal food sources, it is entirely plant based. The upside of being Vegan is that the research shows Vegans to be thinner, have lower serum cholesterol, and lower blood pressure than those on a mixed diet. However, the downside is that by cutting out all animal products from the diet there is an increased risk of certain nutritional deficiencies and this is of concern, especially if you are bringing up children on a Vegan diet.
Studies show how difficult it is for children to get adequate energy and nutrient intake from a plant-based diet! Dutch research found that young children on a strictly Vegan diet had poorer nutritional status and were more likely to have rickets and deficiencies of vitamin B12 and iron than children on a diet that included meat, fish and dairy. It is also worth bearing in mind that The World Health Organization acknowledges that only animal food sources have the potential to provide enough calcium, iron, zinc and vitamin B12 for children.
POTENTIAL NUTRITIONAL SHORTFALLS
I have listed below the six main nutrient shortfalls for vegans. Please read and digest the information because not doing so could jeopardise your health;
VITAMIN B12
Vitamin B12 is the only vitamin that is not available to humans from a plant-based diet. Most herbivores, cattle and sheep, absorb B12 produced by bacteria in their digestive system. Vitamin B12 plays a huge role in the body and we need only 10 mg spread throughout the day to satisfy requirements, that’s less than any other vitamin.
Compared with those on a mixed diet, Vegans typically have lower plasma vitamin B12 concentrations, leading to deficiency, and higher concentrations of plasma homocysteine (an amino acid produced by the body) which increases the risk factor for heart attacks, stroke and osteoporotic bone fractures.
Deficiency symptoms take up to five years to develop in adults, however some people experience problems within a year! Vitamin B12 deficiency causes nervous system damage such as:
Poor co-ordination
Psychoses
Pins and needles
Disorientation
Dementia
Mood and Motor disturbances
Difficulty concentrating
Unusually large red blood cells
A lack of Vitamin B12 in child’s diet can cause apathy and failure to thrive!
Vegan Vitamin B12 Sources
Supplements
Fortified foods
Inadequate Plant B12
Some believe there are plant-based sources of B12, however direct studies of Vegans have shown these sources to be inadequate.
Human gut bacteria
Spirulina
Dried nori
Barley grass and most other seaweeds.
VITAMIN D
The vitamin D2 (the form of vitamin D acceptable to vegans) is substantially less bioavailable than the animal-derived vitamin D3.
According to research from Oxford University, vegans had vitamin D levels one-fourth of omnivores. A study in Finland found that 25-hydroxyvitamin D levels were lower and parathyroid hormone higher in vegan women than in omnivores and other vegetarians. It also found that bone mass density in the lumbar region of the spine was 12% lower in vegans than in omnivores.
Vegan Vitamin D Sources
Vitamin D intake for a vegan depends on sun exposure
Vitamin D-fortified foods. However, check they are Vegan certified because some Vitamin D fortification & supplements are made from the oil of sheep’s wool.
CALCIUM
Calcium is a nutrient that is not only required for healthy bones and teeth but also needed for the nervous system, blood clotting, heart health and muscle function. In fact, we are made up of more calcium than any other mineral! Several studies have shown that bone mineral density, a measure of osteoporosis, is lower in vegans than non-vegans. The current recommended calcium intake for adults aged 19-50 years is around1000 mg per day but research shows that Vegans are taking in between 400-600mg per day. By eating plenty of greens you’ll also be getting vitamin K, potassium, and magnesium, and these all contribute to better bone health.
Vegan Calcium Sources
Dark leafy greens
Okra
Oranges
Figs
Black Strap Molasses
Tahini
Almonds
Although spinach and swiss chard are high in calcium they also contain high levels of oxalate, which helps to get rid of extra calcium by binding with it and prevents absorption from the digestive tract. Too much oxalate can also cause kidney stones.
N-3 FATTY ACIDS
Because the vegan diet doesn’t allow fish or eggs it lacks the long-chain n-3 fatty acids, EPA; and DHA which are important for cardiovascular health, eye and brain functions. Although plant-based n-3 fatty acid, ALA, can be converted into EPA and DHA, it has a very low efficiency leaving vegans, with low blood concentrations of EPA and DHA.
Vegan N-3 Fatty Acid (ALA) Sources
Algal Oil
Flaxseeds
Walnuts
Hemp Seeds
Chai Seeds
Brussels Sprouts
My advice on DHA supplementation is to approach with caution! They may raise cholesterol, cause excessively prolonged bleeding times, and impair immune responses.
IRON
The body needs minerals to help it function too and Iron is an incredibly important one needed to make blood. There are two sources, animals and plants with the most potent and best absorbed from the animal source, Heme iron. However, studies show that because Vegans tend to eat plenty of vitamin C-rich foods the absorption of plant iron is increased. This means that the risk of iron deficiency anaemia in Vegans is similar to those on a mixed diet. That said, the majority of people, worldwide, irrespective of diet have below recommend intakes of iron.
Vegan Iron Sources
Dark green leafy veg
Dark chocolate
Sweet potatoes
Peas
Tofu
Dried fruit: raisins, dates, figs, prunes and apricots
Molasses
Beans
Artichokes
Pumpkin and pumpkin seeds
Nuts
Zinc
Zinc is necessary for various functions, such as fighting infection, growth and speeding up reactions. Vegans are often at risk of zinc deficiency because the Phytates, a component of grains, seeds, and legumes, bind with zinc and decreases its bioavailability. However, with careful planning it is possible to have adequate zinc requirements from eating a balanced vegan diet.
Vegan Zinc Sources
Beans
Chickpeas (helps increase zinc absorption)
Lentils (helps increase zinc absorption)
Tofu
Walnuts
Cashew nuts
Chia seeds
Ground linseed
Hemp seeds
Pumpkin seeds,
Wholemeal bread
Quinoa
FINAL WORD
A vegan diet can be healthy but only if you choose plant-based foods that are varied and balanced. It is especially important to pay attention to the 6 main nutrients that can be easily over looked and put your health at serious risk.
Although it may seem like a practical solution to take these nutrients in supplement form, it's worth considering that nutrients from supplements are not always bioavailable, this means they are not easily absorbed or used by the body for their intended purpose.
If you are vegan or you are thinking of switching to a vegan diet it may be advisable to consult with us at The Green Ward Nutrition to check that you are meeting all your nutritional needs. We can offer science based advice and diet plans to support your vegan choice.
REFERENCES:
Carter, R. (2002). Book Review: Book of the Month: Bodies Politic: Diseases, Death and Doctors in Britain, 1650-1900.
Craig, W. J. (2009). Health effects of vegan diets–. The American journal of clinical nutrition, 89(5), 1627S-1633S.
IOM (Institute of Medicine). Dietary Reference Intakes for Calcium and Vitamin D. Washington, DC: The National Academies Press, 2011.
Mangels, A. R., & Messina, V. (2001). Considerations in planning vegan diets: infants. Journal of the American Dietetic Association, 101(6), 670-677.
Murphy, S. P., & Allen, L. H. (2003). Nutritional importance of animal source foods. The Journal of nutrition, 133(11), 3932S-3935S.
Neumann, C., Harris, D. M. & Rogers, L. M. (2002) Contribution of animal source foods in improving diet quality and function in children in the developing world. Nutr. Res. 22: 193–220.
Sanders, T. A. B., & Manning, J. (1992). The growth and development of vegan children. Journal of Human Nutrition and Dietetics, 5(1), 11-21.
Surdykowski, A. K., Kenny, A. M., Insogna, K. L., & Kerstetter, J. E. (2010). Optimizing bone health in older adults: the importance of dietary protein. Aging health, 6(3), 345-357.
Waldmann, A., Koschizke, J. W., Leitzmann, C., & Hahn, A. (2003). Dietary intakes and lifestyle factors of a vegan population in Germany: results from the German Vegan Study. European journal of clinical nutrition, 57(8), 947.