Optimize Your Nutrient Intake 

Adequate Protein

It is all too easy to replace meat with bread, pasta, and tortillas, but doing so won’t supply the nutrients needed to make up for the loss of the nutrients that meat provides. Protein, composed of amino acids, is available in many whole foods, but humans must obtain specific amino acids from the diet in the proper proportions for the human body. Animal foods like meat, eggs, and dairy supply all of these amino acids in the right proportions—they are considered complete proteins. Plant foods, on the other hand, contain these essential amino acids as well, but not all in one food and in smaller amounts. For vegetarians, foods like eggs, cottage cheese, yogurt, and cheese are all good sources of quality protein. For vegans a variety of foods such as quinoa, hemp seeds, legumes, nuts and seeds, and fermented soy products (like tempeh and miso) all help deliver the essential amino acids, albeit not all in one shot and not in large quantities. It is important to eat a variety of these foods daily to get an adequate supply of protein. 

Avoid Nutrient Deficiencies

American diets are woefully low in many important nutrients like vitamins A, D and E, calcium, and magnesium.¹ Not only do non-meat eaters have to be aware of these common deficiencies, but they are also more prone to other deficiencies. Again, vegetarians fair better then vegans when it comes to getting these essential nutrients, but both are at risk of not only outright deficiencies, but of more subtle, suboptimal levels of nutrients that can interfere with proper bodily function without causing overt deficiency symptoms. 

• Vitamin B12. Among those that don’t supplement, 83 percent of vegans and 68 percent of vegetarians are deficient in B12.² B12 is required for proper nerve function, energy production, immune function, fertility, vascular health, gut health, and brain health, but is only found in animal foods. Humans are able to store B12 in their tissues, so a deficiency can sometimes take years to show up after starting a vegetarian or vegan diet, but children, who lack stores of the vitamin, are especially susceptible. Supplementing with vitamin B12 is absolutely essential for anyone following a vegetarian or vegan diet.

• Minerals are widely distributed in a variety of both plant and animal foods, but many plants contain compounds such as phytic acid and oxalate that bind to minerals, making them unavailable for the human body. Because of this, vegetarians and vegans are encouraged to get more than the RDA for iron and zinc, and vegans should be extra cautious to get enough calcium.³⁴

  • Zinc is essential for proper immunity, blood sugar balance, skin, bone and tissue health, sperm health, and for digestion.⁵ Good non-meat sources of zinc include cremini mushrooms, leafy greens, pumpkin seeds, sesame seeds, and yogurt.⁶

  • Iron is important for energy production and immune function, and those with higher iron needs such as growing children and women of childbearing years may not get enough on a vegetarian or vegan diet. Non-meat sources of iron include legumes, leafy greens, and tofu. 

  • Calcium is necessary for strong teeth and bones and normal functioning of the heart. Without dairy products (the source of most Americans’ calcium), vegans are at a greater risk of calcium deficiency. Calcium is found in a variety of plant sources, but in lower amounts  than dairy products. Leafy greens are a great source but some, like spinach and Swiss chard, have high levels of oxalates that can bind calcium making it unavailable;⁷ however, cooking can reduce some of the oxalates. In general aim to get a variety of leafy greens. 

• Vitamin K2. While closely related, vitamin K1 and K2 do not perform the same functions in the body. Vitamin K1 (found in leafy green vegetables) is primarily involved in blood clotting, but vitamin K2 (found in organ meats, egg yolks, and dairy) is essential for ensuring calcium goes to the right places (bones and teeth) instead of our soft tissues (arteries). Fermented foods like sauerkraut do contain some vitamin K2, but usually only in very small amounts. To ensure optimal levels, it is best to supplement with vitamin K2.

Get Enough of the Right Fats

Those all-important omega-3 fatty acids that we hear so much about can be in short order in a vegetarian diet and non-existent in a vegan diet. Plant sources such as flax and walnuts supply the parent of the omega-3 family, alpha-linolenic acid (ALA), but ALA is only the starting point. ALA goes through a series of conversions in the body to get to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), the fatty acids that actually do all the good things for us. Unfortunately the conversion process from ALA to EPA and then DHA isn’t all that efficient (only about 7 percent is converted to EPA and even less to DHA8) and can be hampered by many things including a poor diet, and conditions such as hypothyroid, diabetes, and atherosclerosis.^{9 10} To further complicate the issue, the conversion is dependent on many different nutrients, some of which may be deficient in a meat-free diet, like B6 and zinc.¹¹ 

To ensure sufficient nutrient intake, vegetarians and vegans would be wise to supplement with a high-quality multi-vitamin and mineral formula, vitamin B12, and an algae-based EPA and DHA supplement. Additional zinc, iron, calcium, and vitamin K2 may also be necessary. 

Boost Brain DHA with Curcumin

Our bodies have the ability to convert the fatty acid alpha-linolenic acid into DHA, but that conversion rate is very low. Enter curcumin. Researchers have found that curcumin, the principal bioactive compound in turmeric, enhances the conversion of alpha-linolenic acid into DHA, helping to increase levels in the brain. The researchers concluded: “These findings have important implications for human health and the prevention of cognitive disease, particularly for populations eating a plant-based diet or who do not consume fish…” ¹²

Avoid the Common Pitfalls 

Not only do vegetarians and vegans have to contend with many of the same dietary pitfalls as meateaters (junk foods, chemically modified fats, hidden sugars, etc.), but there is also a whole host of things to consider about the foods that fill the meat void. 

• The first are grains and legumes which tend to make up a heavy portion of the diet. Unfortunately, for those trying to lose weight or for those with gut issues or autoimmune conditions, a diet heavy in grains and legumes can be damaging. Even for an otherwise healthy person, grains and legumes are high in anti-nutrients such as phytates, which interfere with mineral absorption. Any diet that relies heavily on these foods should consider proper cooking techniques such as soaking and sprouting to improve digestibility and reduce phytate levels. 
• Soy is another place for concern. Although soy is high in protein for a plant food, it comes with a dark side. Too much soy can interfere with thyroid function and mineral absorption. It is also high in phytoestrogens which may interfere with the body’s own hormones, especially in growing children and men. Ideally soy should be consumed in moderation, and stick to organic versions of traditionally prepared and fermented forms like miso, tempeh, and soy sauce.
• The final place those avoiding meat should be cautious is with meat and dairy substitutes. Today, everything from fake bacon to soy cheese and hotdogs are readily available, but beware, these products are usually very highly processed. While they can make a fun occasional substitute, they should never form the basis of the diet.

Whether you’re just venturing into a vegetarian or vegan diet or if you have been following the diet for years and have fallen into a rut, a bit of forethought, preparation, and maybe a little bit of revamping will take you a long way. And just like with any diet, whole, unprocessed foods and a few natural supplements help to ensure that you are as healthy as you can be.

References  

1. Fulgoni VL, Keast DR, Bailey RL, Dwyer J. Foods, fortificants, and supplements: Where do Americans’ get their nutrients? J Nutr. 2011;111:142257. 
2. Herrmann W, Schorr H, Obeid R, Geisel J. Vitamin B12 status, particularly holotranscobalamine II and methylmalonic acid concentrations, and hyperhomocysteinemia in vegetarians. Am J Clin Nutr. 2003;78(1):131-136.
3. n.a. Iron Fact Sheet. National Institutes of Health. February 19, 2015. Available at: http://ods.od.nih.gov/factsheets/IronHealthProfessional/#h6. Accessed May 18, 2015.  
4.  n.a. Zinc Fact Sheet. National Institutes of Health. June , 2013. Available at: http://ods.od.nih.gov/factsheets/ZincHealthProfessional/#h6. Accessed May 18, 2015.  
5. Masterjohn C. Vegetarianism and Nutrient Deficiencies. Weston A. Price Foundation. May 7, 2009. Available at: http://www.westonaprice.org/health-topics/abcs-of-nutrition/vegetariani…; Accessed May 18, 2015. 
6. Mateljan G. The World’s Healthiest Foods. Seattle, WA: George Mateljan Foundation; 2007. 
7. Weaver CM, Proulx WR, Heaney R. Choices for achieving adequate dietary calcium with a vegetarian diet. Am J Clin Nutr. 1999; 70(3):543s-549s. 
8. Goyens PLL, Spilker ME, Zock PL, Katan MB, Mensink RP. Compartmental modeling to quantify alpha-linolenic acid conversion after longer term intake of multiple tracer boluses. J Lipid Res. 2005;46:1474-1483.
9. Briggs S. Flaxseed Oil CLF. Natural Grocers by Vitamin Cottage. April 2008
10. Das UN. Essential fatty acids: biochemistry, physiology and pathology. Biotechnology Journal. 2006;1(4):420-439. 
11. Briggs S. Flaxseed Oil CLF. Natural Grocers by Vitamin Cottage. April 2008. 

12. Wu A, Noble EE, Tyagi E, et al. “Curcumin boosts DHA in the brain: Implications for the prevention of anxiety disorders.” Molecular Basis of Disease. May 2015;1852(5): 951-961 https://doi.org/10.1016/j.bbadis.2014.12.005