A properly planned vegetarian or vegan diet has the potential to provide total nourishment as well as prevent and treat certain diseases. It is important to ensure adequate variety and proper food pairings in order to accomplish the above because the likeliness of iron, zinc, B12, iodine, calcium, and vitamin D deficiency is increased for vegans and vegetarians. Let’s start with iron.
Iron is a mineral that is found in many proteins and enzymes in the body and also plays a role in the transport of oxygen. Iron from plant sources is less readily absorbed than from animal sources and is also vulnerable to factors inhibiting its absorption, such as pytate and polyphenols in tea, coffee, en cocoa. Therefore, it is important for those who exclusively eat plant sources to take caution.
Techniques for Better Iron Absorption
Some cooking/food combination techniques to help increase plant iron absorption and bioavailability include:
- The leavening of bread (releases the phosphorus bond)
- Fermentation of miso and tempeh (breaks down phytate)
- The sprouting of beans, grains, and seeds (reduces phytate)
- Consuming vitamin C food sources with non-heme iron sources (counteracts phytate)
- Drink tea and coffee in between meals (instead of during meals)
- Do not combine chocolate with an iron rich meal or snack (wait at least 30 minutes)
- When combining raw spinach with an iron-rich meal, use vinegar as a dressing
Those at higher risk of iron deficiency include: women (due to blood loss during menstruation), women who are pregnant, and premature/low birth weight infants. If you notice complaints such as those listed below and/or do not have a varied diet, I recommend that you seek a docter or dietitian to discuss the possibility of iron deficiency. Iron deficiency can be detected through routine laboratory tests including hemoglobin, hematocrit, and serum ferritin.
Symptoms of iron deficiency:
- Easily fatigued
- Pale skin
- Shortness of breath
- Restless leg syndrome
- Concentration problems
- Fingernails can become thin and flat
Coincidentally, studies have actually shown that iron-deficiency anemia incidence among vegetarians is similar to that of non-vegetarians. Although the notion that vegans/vegetarians must aim for 1.8x the iron RDA of non vegetarians was based on a single poorly designed study, it remains widely recommended that vegans/vegetarians should strive for higher iron intakes than non vegetarians.
More interesting literature follows regarding the possible benefits of having a lower serum ferritin (a measure of the amount of stored iron) level including decreased risk of type II diabetes, coronary artery disease, and colon caner. Furthermore, recent studies show a link between excess iron stores with Alzheimer’s, Parkinson’s disease, arthritis, type II diabetes, cardiovascular disease, and colorectal cancers. By consuming the nonheme iron form found in plants, your serum ferritin level remains low (replenishing itself as needed), and iron overload is avoided. Plants seem to be pulling ahead!
Stay tuned for the next article over the popular topic: B12 supplementation.
Mahan, L., & Escott-Stump, S. (2011). Nutrition and Bone Health. In Krause’s Food & Nutrition Therapy (13th ed., pp. 614-635). St. Louis, MO: Saunders/Elsevier.
Davis, Brenda, RD & Melina, Vesanto, MS, RD. (2014). Minding Your Minerals. Becoming Vegan Comprehensive Edition (1st ed., pp. 4106-4736). Summertown, TN 38483: Book Publishing Company.
Mangels AR et al. The Dietitians Guide to Vegetarian Diets. Jones and Bar