Vegan Nutrition with Marty Davey

I've been vegan for about a year now and take vitamins/supplements but was wondering exactly what supplements are essential to take everyday and how much of each vitamin (i.e. mg's or IU's) I should be taking to sustain long term health. I'm 20 and don't want to regret being vegan years down the road when I'm suffering health issues/deficiencies.

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When discussing supplements with vegan dietitians, you are one step away from bringing up religion and playing hopscotch in a mine field. However, I grew up in a family of folks never fearing to give their opinions, so let me spout my personal dogma and hope my armor of research protects me.

I agree with Brenda Davis, RD and Dr. Michael Gregor, who say that vegans and vegetarians need to take vitamin B12 and Docosahexaenoic Acid [DHA], and vitamin D on a daily basis. I would suggest getting tested for these, especially the vitamin D before supplementing. During the summer, I'm outside a lot. Come September, my schedule moves indoors and I take vitamin D.

Vitamin B12 - You need this to complete a metabolic conversion. Metabolic conversion means you take Substance A - add or subtract stuff to convert it to Substance B - add or subtract stuff to convert it back to Substance A. The Substance B in this case is Homocystiene. Homocysteine is a naturally occurring substance in your body. Like lots of stuff in your body, a little is good, but a lot can be a problem. Homocystiene is also a neural and vascular toxin which can build up without enough B12. B12 is the stuff you add to convert the homocysteine in to a usable amino acid. Many researchers have shown that vegetarians, vegans and folks over the age of 50 have an elevated level of homocysteine and a deficiency of the usable amino acid. The food [I use the word "food" loosely] sources of this vitamin are only in animal products.

I know there are those of you who claim nutritional yeast, nori, dulse or tofu as sources. The research does not hold up. The possibility of debilitating deficiency health issues outweighs my fear of taking a pill and not being "natural".

To ensure you have enough B12 for the conversion, take either 1000mcg two times a week, or 50-100mcg daily. THIS IS THE IMPORTANT PART: Take this sublingually. That means under the tongue. Let it dissolve. Even if you can't find supplements specifically made to be taken sublingually, crack them with your teeth, put them under your tongue and let melt. Jack Norris, RD, has the most detailed information on B12. Read it and decide for yourself. http://www.veganhealth.org/b12/

DHA - This is an essential fatty acid. Essential means that you must eat them. Your body cannot synthesize them from anything. There are two of these types of oils. The first is the precursor, or maker, of DHA. The precursor is called alpha-linolenic acid (ALA), the omega-3 we all hear about. You can find this in flax meal and walnuts. Use 2 tablespoons of flax meal [n9ot seeds], and eat an ounce or two of walnuts daily.

The other oil is linoleic acid (LA). That is the omega-6 family. You find this in sesame seeds, corn oil and nuts.

The conversion of ALA to DHA can be inhibited by transfats. Conversion of ALA to DHA may nor may not happen as quickly from plant foods as animal foods. There is good research to support both ideas. But, I err on the side of caution.

To maximize DHA levels daily intake should be 100-300 mg/day. Be sure that the source of the DHA/EPA is from microalgea. This is the vegan source. Fish oil has DHA. However, taking fish oil not only depletes the ocean of inhabitants, but smells bad after it breaks down in your stomach.

Vitamin D - I know that you get vitamin D from the sun, but we aren't out in the sun the way we used to be. In addition, we use sunscreen more which decreases vitamin D synthesis. There was a study done in Hawaii, and one in Arizona which showed that even folks in these sunny climates had a significant vitamin D deficiency.

Dr. Paulette Chandler, of Brigham and Women's Hospital in Boston, suggests 400 IU of vitamin D daily. This is the same recommendation as Brenda Davis, RD. Actually, there are a lot of vegan healthcare practitioners who recommend this, including me. Again, make sure it is from a vegan source. Ergocalciferol is the upscale, scientific, snazzy name for vitamin D2. Vitamin D2 is a vegan source. Cholecalciferol or vitamin D3 is not.

These are the supplements that have been recommended at every conference I attend with research to back up their use, consequently, I use them. But, I am not married to them. We have seen a lot of studies and trends come and go. Make sure you are doing your own research, because it is ultimately your own health.

Marty Davey is a Registered Dietitian and has a Masters degree in Food and Nutrition from Marywood University. She became a vegetarian in 1980 when she discovered that the chemicals in American meat made them unsellable to Europeans. She and her husband have raised their son as a vegan. She teaches nutrition and has a private practice specializing in assisting clients transitioning to a plant-based regime step by step. Her website is martydavey.com

Get your own personal nutrition consultation with Marty here.

Disclaimer: The advice given here is for eductional purposes only. You should not use this information to diagnose or treat a health problem or disease without consulting with a qualified health care provider.

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