Vitamins with a complex a simple rundown on the Bs - wellness

Better Nutrition, Jan, 2003 by Michael Smith

Run your finger down the side of a cereal box or across a bottle of multivitamins, and you'll find them--familiar words such as riboflavin, folic acid and niacin. But while we've all heard of them and were convinced--somehow and long ago--that they're very important, what are they really? And who, in particular, needs to pay attention to them?

Folio and pantothenic acids, biotin, vitamins [B.sub.6] and [B.sub.12]--each belongs to the team of eight distinct vitamins called the "B complex," so named because they are usually taken as a group. Common sources of B-complex vitamins include liver, rice, nuts, milk, eggs, meats, fish, fruits and leafy green vegetables.

"Keep in mind, though, that these are all individual nutrients," says Barbara Lohse Knous, professor of Human Nutrition at Kansas State University. "We do know that they work together and are involved in helping the body and metabolism function, but each works and interacts with other nutrients and proteins very differently."

Within the Bs, the most common deficiency is [B.sub.12] (cyanocobalamin). "That's something you'll see with strict vegetarians," says Cynthia Frozena, a medical researcher and writer at Enzymatic Therapy, a manufacturer of B supplements. [B.sub.12] isn't found in any plant foods, so supplements are a good idea for vegetarians."

Problems with the absorption of [B.sub.12] can also occur as we age, so the elderly can be at risk for this deficiency. Symptoms include weakness and numbness in the extremities. "There's also a lot of evidence and research to suggest that [B.sub.12] plays a role in general cognitive functioning," says Knous.

"And you can often tie problems with lack of energy and fatigue to low levels of [B.sub.12]," says Allan Spreen, MD, a nutrition counselor and author of Folio Acid: The Essential B Vitamin and Nutritionally Incorrect. "It's a pretty common complaint, and about one out of three times, a boost of [B.sub.12] helps."

[B.sub.12] interacts closely with folic acid ([B.sub.9]), a particularly important vitamin during pregnancy. "Folio acid is an especially vital nutrient for fetal neurological development, so women should maintain good folic acid status long before pregnancy occurs," says Knous, noting that the nutrient plays its role in development very early--around day 17--often before a woman is even aware of the pregnancy. Doctors usually recommend a folio acid supplement of 300 milligrams leading up to and during pregnancy.

Vitamin [B.sub.6] (pyridoxine) can also be important for pregnant women. "It was practically considered witchcraft a few years ago, but taking [B.sub.6] has been shown to help women with morning sickness and with swelling in the hands and feet," says Spreen. "We've also had great results with improving carpal tunnel syndrome and other wrist and joint problems by boosting [B.sub.6]"

There's increasing evidence to suggest that [B.sub.6], along with folio acid and [B.sub.12], also plays a part in the prevention of heart disease. Research shows that high-protein diets result in increased homocysteine, an amino acid by-product of protein metabolism. The concern is that elevated homocysteine levels cause damage to arterial walls, preventing the expansion of blood vessels and escalating the risk of stroke and heart disease. This supports a theory that has been slow to gain acceptance: A high-protein diet--more than fats and cholesterol--is a contributor to heart disease.

"One way to keep your homocysteine level down is to keep it properly metabolized through vitamin [B.sub.6], often combined with folio acid and vitamin [B.sub.12]," says Knous.

Like anything else, an overabundance of any of the B vitamins can be too much of a good thing. Mega-doses of folio acid, for example, can cause convulsions. Extreme amounts of pyridoxine can bring on nerve damage. And too much pantothenic acid results in diarrhea. "Some people experience a kind of flush when they take niacin to help with blood flow--their faces will get very red, they may feel warm or slightly feverish," says Frozena. Niacin's "10-minute sunburn" isn't dangerous, although it can be unnerving the first time it happens.

"Still," says Spreen, "the chances of getting in trouble by taking too much of a specific vitamin are remote compared to the problems caused by not having enough."