Vitamin Supplements

In general, vitamin C appears to be relatively safe for most people, even when consumed in fairly large quantities over long periods of time. Doses as high as 10 g per day (more than 100 times the RDA) for several years do not have any toxic effect for some people. The body tends to excrete (in the urine) any vitamin C it can’t put to use, thereby preventing toxic buildup. Some studies, however, have shown that toxic symptoms can occur in daily doses of as little as 1 g. Read the rest of this entry »

Before you decide that you need to take vitamin supplements or change the way you eat, you should know where you stand and how much improvement you really need. To help you analyze your current diet, we’ve developed a system you can use to calculate your approximate vitamin C intake. Following is a list of vitamin C food sources, arranged according to the percentage of our Optimal Daily Allowance of vitamin C contained in them. Read the rest of this entry »

If you answer yes to any of the following questions, you have an above-average risk of developing a vitamin C deficiency.

• Do you smoke? Studies show that smokers need at least twice as much vitamin C as nonsmokers, because smoking increases the rate of breakdown of this vitamin.

• Are you an older person? Older people often take medications that enhance the breakdown of vitamin C. In addition, many older people have poor dietary habits—sometimes because they are on limited budgets or Read the rest of this entry »

At one time vitamin B was thought to be one single substance. Now we know there is a whole family of these vitamins, more than a dozen of them. We refer to them as the B complex vitamins. They are often found together in various foods. But they are all different in their effects upon the human body. Some are needed in the transfer of energy within the cells. Others are required for the formation of red blood cells. But they have other activities as well. Read the rest of this entry »

There are many different vitamins, all having their own particular function to carry out. Research workers in many lands are searching for the answers. Just when they think the final answer is at hand, a whole new vista opens before them. Vitamins are close to the secret of life itself.

Contrary to what many may think, a vitamin is not a food. If you ate vitamins and nothing else, you would starve to death. Nor do they provide energy to build up worn-out tissues. Then why are they so important? Because without them no life could exist in either plants or animals. They are the catalysts, or “go-betweens,” that bring about all the innumerable chemical reactions within the body. Read the rest of this entry »

Among the most exciting findings of modern times is the discovery of vitamins. Until a few years ago no one even dreamed of their existence. For centuries it had been observed that during long ocean voyages sailors often came down with a mysterious disease called scurvy, which affected the skin, the gums and teeth, and other parts of the body. This disease usually cleared soon after the sailors reached land and began to eat fresh fruits and vegetables. Read the rest of this entry »

Vitamin D is not like other vitamins. Because the body can manufacture this nutrient, in fact, vitamin D fails to meet the classic definition of a vitamin. Vitamin D is manufactured in the skin, with ultraviolet light driving the process. With regular exposure to sunlight, most people can manufacture enough of this vitamin to meet all of their needs. People who do not get enough year-round exposure, however, may require dietary D as well. Certain groups, including older people, have difficulty producing vitamin D themselves and may also require dietary D.

While rickets, a disease caused by a vitamin D deficiency, has been around for thousands of years, our knowledge of the vitamin itself has a relatively short history. It was first isolated and synthesized. Read the rest of this entry »

If you answer yes to any of the following questions, you (or your child) have an above-average risk of developing a vitamin D deficiency.

• Are you an older person? Skin production of vitamin D tends to slow down with age. Studies of older people—particularly older women—show that as many as 75 percent are at marked risk for vitamin D deficiencies.
• Are you confined indoors and not exposed to sunlight? With limited sun exposure, your skin will produce a minimal amount of vitamin D, leaving you to rely on diet alone for your vitamin D needs.
• Do you have kidney or liver disease? Vitamin D, formed in the skin, must be modified chemically in the kidney and liver before the body can use it. This process can be severely impaired if these organs are diseased. Read the rest of this entry »

Recommended Daily Allowances for vitamin D are given here in both micrograms and international units. The IU is a common unit of measurement among many vitamin supplement manufacturers. Remember that people who get enough sunlight do not need additional vitamin D.

Vitamin D Optimal Daily Allowance

We recommend an optimal daily allowance of 400 IU of vitamin D per day. Fewer foods are rich in vitamin D than in other vitamins and minerals, so you may need to take a vitamin D tablet to supplement your diet. Read the rest of this entry »

Before you decide that you need to take vitamin supplements or change the way you eat, you should know where you stand and how much improvement you really need. To help you analyze your current diet, we’ve developed a system you can use to calculate your approximate vitamin D intake. Following is a list of vitamin D food sources, arranged according to the percentage of our Optimal Daily Allowance of vitamin D contained in them. Since 3 ounces of tuna canned in oil contain 197.2 IU of vitamin D and the ODA for vitamin D is 400 IUD, we’ve listed tuna in the 50 Percent category. Read the rest of this entry »