Vitamin Information Center

CHOLESTEROL
Cholesterol is a waxy substance found in the fats (lipids) in our blood. It is manu-
factured in the liver and also obtained from consuming saturated and trans fats.
Cholesterol is not all bad—the body requires it to produce sex hormones, maintain
cell membranes, and for a healthy nervous system. 12 | Chapter 1
Aside from diet, cholesterol levels can be elevated by family history, lack of ac-
tivity, and liver disorders, and cholesterol consumption increases the risk of heart
disease.
As with fats, there is good and bad when it comes to cholesterol. The good
cholesterol is HDL (high-density lipoproteins) and the bad is LDL (low-density li-
poproteins). LDL cholesterol can build up in the artery walls of the brain and heart,
narrowing the passageways for blood fl ow, a process known as atherosclerosis, the
precursor to heart disease and stroke.
HDL cholesterol is called good cholesterol because it picks up the LDL deposited
in the arteries and transports it to the liver to be broken down and eliminated.
To lower LDL and raise HDL levels, exercise regularly, minimize saturated fats,
avoid trans fats, and don’t smoke (smoking lowers HDL).

By Will Dunham

WASHINGTON (Reuters) - Vitamin D may protect against an artery disease in which fatty deposits restrict blood flow to the limbs, researchers said on Wednesday.

Scientists at the Albert Einstein College of Medicine of Yeshiva University in New York found that people with low levels of vitamin D in their blood experience an increased risk for a condition known as peripheral artery disease, or PAD.

PAD most often reduces blood flow to the legs, causing pain and numbness, impairing the ability to walk and in some cases leading to amputation. It develops when fatty deposits accumulate in the inner linings of artery walls, cutting blood flow and oxygen to the legs, feet, arms and elsewhere.

The researchers based the findings on a U.S. government health survey involving 4,839 adults who had their blood vitamin D levels measured and underwent a screening method for PAD that assesses blood flow to the legs.

The people in the lowest 25 percent of vitamin D levels were 80 percent more likely to have PAD than those in the highest 25 percent, the researchers said.

“Participants in the survey who had the lowest vitamin D levels had a much higher prevalence of peripheral artery disease,” Dr. Michal Melamed of Albert Einstein College of Medicine, who led the study, said in a telephone interview.

But Melamed said it would be premature for people to start taking vitamin D supplements because more studies are needed to confirm that it is protective.

Melamed noted that other vitamins that had been thought to possibly help prevent cardiovascular disease such as vitamin E did not pan out after further research.

The study was presented at an American Heart Association meeting in Atlanta and was published in the association’s journal Arteriosclerosis, Thrombosis and Vascular Biology.

Vitamin D helps the body absorb calcium and is considered important for bone health. In adults, vitamin D deficiency can lead to osteoporosis, and it can lead to rickets in children.

Some studies have indicated it might provide other benefits. For example, one published in January found that people with low vitamin D levels had an elevated risk for heart attack, heart failure and stroke, suggesting the vitamin may protect against cardiovascular disease.

The body makes vitamin D when skin is exposed to sunlight. It is found in fatty fish such as salmon. Milk commonly is fortified with it.

People with PAD have a four to five times greater risk of heart attack or stroke, according to the American Heart Association. The group said 8 million Americans have PAD.

(Editing by Xavier Briand)