B vitamins are unsung heroes of good health
Two of the B vitamins, biotin and pantothenic acid, tend to be underappreciated. The common assumption that we consume plenty of these B vitamins might not always be true.
Question: Are biotin and pantothenic acid important for health?
Answer: Yes. Both biotin and pantothenic acid are essential to ensure that cells can get energy from carbohydrate, fat, protein and alcohol. In addition, biotin plays a role in how genes function. Consequently, biotin deficiency causes birth defects in laboratory animals and might play a role in some human birth defects.
Q: Do people get enough of these two vitamins?
A: It appears that most of us get plenty of pantothenic acid, but it is not so clear for biotin. Obvious symptoms of deficiency of either vitamin have only been observed in people being tube-fed or in those consuming extremely limited diets. But the gap between clearly deficient intake and optimal intake remains yet to be discovered.
New developments in biotin research have questioned the adequacy of biotin in the diets of some people, particularly pregnant women and seniors. UC-Berkeley professor Bruce Ames and his colleagues have shown that to maintain normal function, older human cells grown in laboratory conditions need more biotin than younger cells grown under the same conditions. Ames has stressed that much more study of the optimal biotin intake is needed for all age groups.
Q: How much biotin is in our foods?
A: A few years ago, researchers from the U.S. Department of Agriculture asked this question. Since the existing information on the biotin content of foods was limited and old, the scientists used modern techniques to measure the biotin in more than 80 foods. They found that most of these foods had much less biotin than previously thought. Consequently, previous studies of how much biotin people consume would have significantly overestimated the biotin in their diets.
Q: How much pantothenic acid and biotin do we need?
A: The adult recommended intake for pantothenic acid of 5 milligrams (mg) per day is easily obtained by consuming normal amounts of common whole foods. Supplements labeled with 100 percent of the Daily Value provide 10 mg of pantothenic acid -- twice the current recommended intake.
Recommended adult biotin intake is 30 micrograms (mcg) per day. If a supplement label indicates 100 percent of the Daily Value, it contains 300 mcg -- 10 times the current recommendation. According to the new biotin food data, foods rich in biotin include eggs, most lean meats, some fish such as salmon, and some nuts and seeds like peanuts and sunflower seeds.
Alan Titchenal, Ph.D., C.N.S. and Joannie Dobbs, Ph.D., C.N.S. are nutritionists in the Department of Human Nutrition, Food and Animal Sciences, College of Tropical Agriculture and Human Resources, University of Hawaii-Manoa. Dr. Dobbs also works with University Health Services.