Research Tips

May 19, 2009
Vegetarian diets are not always healthy. Whether you consume animal products or not, consuming a good balance of essential nutrients is more important than what the diet excludes.
Am J Clin Nutr. 2009 May;89(5):1607S-1612S.


November 10, 2009
Vegetarians are prone to vitamin B-12 deficiency, therefore if you are a vegetarian, it is important to consume a high dose supplement of vitamin B-12.
Ann Nutr Metab. 2000;44(5-6):229-34


June 16, 2010
Studies on people consuming vegan and macrobiotic diets have reported poor vitamin B-12 status in as many as 90 percent of the study participants. Diets free of animal foods require adequate B-12 from supplements or fortified foods.
Ann Nutr Metab. 2000;44(5-6):229-34.


July 8, 2010
The breast-fed infant of a healthy mother can thrive on breast milk alone for four to six months. However, if a mother is deficient in vitamin B-12, her milk also will be deficient. This can irreversibly damage the baby's brain and nerve development. Consequently, vegetarian mothers are commonly advised to take a B-12 supplement.
Nutr Rev. 2008 May;66(5):250-5.


January 18, 2011
The book titled the “China Study” promotes a completely plant-based diet free of meat, fish, or milk. The author, however, fails to discuss his own published research from the “China Study.” His research demonstrated clear benefits of milk consumption on bone health in the Chinese population.
Am J Clin Nutr. 1993 Aug;58(2):219-27.


February 4, 2011
A vegan diet can provide health benefits, but this diet has specific risks like virtually all styles of eating. The major nutritional limitations of a vegan diet appear to be low intake of omega-3 fatty acids, vitamin B-12, and iron.
J Agric Food Chem. 2011 Feb 9;59(3):777-84.


June 7, 2011
A recent Boston study indicated that those consuming a vegan diet had low levels of urinary iodine, indicating a low dietary iodine intake. Low iodine status in a woman is especially risky for her developing fetus and for her infant during breastfeeding.
J Clin Endocrinol Metab. 2011 May 25. [Epub ahead of print]


September 20, 2011
As a group, vegetarians are thought to have a lower risk of cardiovascular disease than their omnivorous counterparts. However, vegetarians do contract heart disease. Vegetarian diet risk factors include a low intake of vitamin B-12 and omega-3 fatty acids.
J. Agric. Food Chem., 2011, 59 (3), pp 777–784.


April 5, 2012
Well designed vegetarian diets can be healthful. However, avoidance of specific food groups does increase the risk of nutritional inadequacy. For example, in many types of vegetarian eating patterns, iron can be low and/or in forms that are poorly absorbed.
J Nutr. 1950 Jul;41(3):433-46.


July 1, 2012
Desire for more environmentally friendly protein options has increased the number of meat-alternative products. Selecting products that make sense as plant-based meat alternatives requires reading the nutrition facts panel to assure adequate protein. Ideally, a meat substitute should contain at least 15 grams of protein per serving.
Am J Clin Nutr. 2007 Apr;85(4):960-6.


August 6, 2012
People select vegetarian diets for many good reasons. However, new research indicates that it is common for people with eating disorders to use vegetarianism as a more socially acceptable way to avoid eating many foods.
J Acad Nutr Diet. 2012 Aug;112(8):1247-52.


March 14, 2015
Breast milk of vegetarian mothers can become deficient in vitamin B-12. Because B-12 is needed for infant brain and nerve development, vegetarian women should be especially careful to meet their B-12 needs with supplements or fortified foods.
Nutr Rev. 2008 May;66(5):250-5.


March 16, 2016
Vitamin B12 Deficiency: Research indicates that the prevalence of vitamin B12 deficiency is quite high in people who have consumed vegetarian diets for years. Consequently, vegetarians, and especially vegans, should either have periodic testing for deficiency or take a vitamin B12 supplement.
Nutr Rev. 2013 Feb;71(2):110-7.


March 23, 2016
Vegan Diet: A study in Finland analyzed the diets and nutritional status of those consuming a vegan diet. They found that the vegans should be including dietary supplements for nutrients like vitamins B12 and D, as well as iodine and selenium. Also interesting, the vegans had higher iron intake than the non-vegetarians, but blood measures of iron status were lower in the vegans. This is likely due to the low iron bioavailability in plant foods.
PLOS ONE, 2016;11(2):e0148235.


April 1, 2016
Ancestry and Vegetarian Diet: A new study found that people from populations that historically have consumed primarily vegetarian diets are genetically better at converting the omega-6 fatty acid found in many plant foods (linoleic acid) to the longer and more metabolically active essential fatty acid molecule found primarily in animal fats (arachidonic acid). This may be one of many reasons why some people fare better on vegetarian diets than others.
Mol Biol Evol. March 29, 2016. [Epub ahead of print]


September 19, 2016
Vegan Diet: A completely vegan diet lacks vitamin B12 unless it includes foods fortified with the vitamin. Many other nutrients can be inadequate unless foods are carefully selected for the right variety. The long-chain omega-3 fatty acids present in fish oils also are not provided by a vegan diet unless in includes certain algae oil supplements. These fatty acids are especially essential for brain and retina health. The damage to health from B12 and long-chain omega-3 fatty acid deficiencies can take decades to become apparent.
Ernahrungs Umschau 63(04): 92–102.


February 12, 2017
Limitations of a Vegan diet: A vegan diet can provide health benefits, but this diet has specific risks like virtually all styles of eating. The major nutritional limitations of a vegan diet appear to be low intake of omega-3 fatty acids, vitamin B-12, and iron.
J Agric Food Chem. 2011 Feb 9;59(3):777-84.