When we talk about a healthy diet, the first thing that comes to mind is eating vegetables and fruits. Plant-based foods are indeed an integral part of a healthy diet, but to ensure that you get all the nutrients you need from food, you need variety and balance. Following a strict plant-based diet puts a person at risk for nutrient deficiencies as certain nutrients cannot be derived from plants alone.
For instance, vitamin B12 in its natural form can only be obtained from animal sources such as meat, fish, dairy products and eggs. Hence, vegetarians and vegans are at higher risk for vitamin B12 deficiency. As we age, we are more likely to become deficient in vitamin B12 because our ability to absorb it is reduced. Studies show that a large percentage of vegans and many American adults have suboptimal levels of this essential vitamin. About 10 to 30% of older adults cannot efficiently absorb vitamin B12. Neurological changes in people 50 years and older have been associated with vitamin B12 deficiency.
Vitamin B12 is often referred to as the “energy vitamin” because of its role in energy production. It is also important for red blood cell formation, nervous system development and DNA synthesis. Deficiency in this vitamin is a serious nutritional concern as it can lead to loss of energy, numbness, excessive fatigue, nervous system damage and megaloblastic anemia. Low levels of vitamin B12 can also increase levels of homocysteine. Even a slight elevation in homocysteine levels increases the odds of developing heart disease and stroke as it promotes blockage in arteries. Vitamin B12 deficiency is also associated with psychiatric disorders, including mood disturbances, depression, irritability, memory loss, cognitive decline, Alzheimer’s disease and other dementias. Such conditions develop gradually and symptoms are often manifested after five or more years of inadequate vitamin B12 intake. Although most vegans consume enough vitamin B12 to prevent cognitive problems and anemia, their intake may not be sufficient to avoid pregnancy complications and heart disease.
Most cases of vitamin B12 deficiency are reversible with appropriate supplementation. People following a strict vegan diet can obtain vitamin B12 from nori seaweeds (raw or freeze-dried) and tempeh, as well as from fortified foods. Processed foods, on the other hand, are not recommended sources, as they may contain chemicals that can adversely affect health. Vegans and adults 50 years and older are advised to use supplements to meet vitamin B12 requirements.
Vitamin B12 supplements can boost energy and endurance, improve mood, enhance concentration and even strengthen the immune system. They may also provide protection against certain types of cancer, diabetes and cardiovascular disease, and be useful in treating male infertility, sleep disorders, depression, mental conditions and asthma. Some forms of vitamin B12 are better absorbed than others. Partner with your doctor to find what works best for you.
References:
http://articles.mercola.com/sites/articles/archive/2015/08/03/vegetarian-vegan-nutrient-deficiencies.aspx
http://www.veganhealth.org/articles/everyvegan
http://www.livescience.com/47398-vitamin-b12-deficiency-supplements.html
http://www.webmd.com/food-recipes/20030618/vegetarian-diet-b12-deficiency
http://www.veganhealth.org/articles/vitaminb12
http://vegetariannutrition.net/docs/B12-Vegetarian-Nutrition.pdf