Vitamin Information

The vitamin information in this brief and incomplete guide covers:

	vitamin benefits -what vitamins can do for you
	vitamin dosage or RDA - Recommended Daily Allowance
	vitamin overdose or toxicity
	vitamin deficiency

You can click the links below to find information about:

	Vitamin A
	Vitamin B6
	Vitamin B12
	Vitamin C
	Vitamin D
	Vitamin E
	Vitamin K

I have compiled most of the vitamin information on this page from the MedlinePlus sites and the Office of Dietary Supplements.Go there if you like more details. Both are official US National Health Institute sites. The RDA's quoted are from these sites and are for adults.

Before you self diagnose your supplement needs do yourself a favour and discuss it with your health care provider.

Naturally Direct offers a range of good quality single vitamin products which are free of preservatives, fillers or artifical colors. 

Dietary supplements are not analyzed by the U.S. Food and Drug Administration (FDA) but from June 2010 onwards have to comply with Good Manufacturing Practices (GMP) issued by the FDA.

Vitamin A

Also know as Beta-Carotene or Retinol - is good for your vision, bone growth and your immune system. Recent research suggests that it helps to prevent some types of cancer.

The RDA (Recommended Dietary Allowance) for an adult is 3,000 IU (International Unit) for a male and 2,310 IU for a female and can easily be covered by eating a carrot (about 9,000 IU) or some spinach. Actually our bodies can absorb vitamin A from animals more efficiently than from plants - if you like beef liver.
Vitamin A deficiency is hardly a concern in the Western world.

Too much of a good thing can lead to a chronic toxicity. The suggested Upper Intake Level is at 10,000 IU.

Vitamin B6

Or Pyridoxine - is essential for your protein and red blood cell metabolism and helps your immune system.

The RDA is between 1.3 and 1.7 mg and can be covered with eating a serving of fortified cereals or 2 baked potatoes.

Vitamin B6 is often mildly lacking, while a too high dose mainly from supplements can lead to reversible nerve damage in limbs.

Vitamin B12

(Cobalamin) is needed to keep nerve cells and red blood cells healthy and to make DNA. A study suggests that multi-vitamin supplements can decrease homocysteine level, which is a risk factor for cardiovascular disease.

B12 deficiencies are rare but can occur due to an inability to absorb the vitamin. Older people are more at risk for that to happen. Untreated deficiencies can cause permanent nerve damage and has been linked to dementia. Folic acid can hide the lack of B12 and should therefore be taken in moderation (<1,000 mcg per day).

The good news is that the IOM says that you can't overdose on B12.

Vitamin B12 is found in meat and fish and in some fortified cereals. The RDA is at about 2.4 mcg for an adult.

Vitamin C

The body requires Vitamin C (Ascorbic Acid) to produce collagen, cartilage, muscle and blood vessels and to help with the absorption of iron. On top of that it is an antioxidant. The jury is still out on what it can achieve in that function, but it's promising.

As everybody knows Vitamin C is available in fruits (like plenty in oranges) and in veggies. Actually red peppers are full of vitamin C and so are kiwi fruit. Orange juice only covers the recommended dose when freshly squeezed.

In the old seafaring days scurvy was a common consequence of Vitamin C deficiency. RDA for grownups is between 75 and 90 mg, smokers need 35 mg per day more to make up for their sins.
Although a max intake of 2,000 mg is suggested, an 'overdose' is unlikely to cause any serious side effects.

Vitamin D

Is important to maintain the level of calcium and phosphorus in the blood and it is required for calcium absorption, which is needed for strong bones. Vitamin D might even offer some protection from osteoporosis, cancer, high blood pressure and autoimmune diseases - but that hasn't been confirmed yet.

Forms of Vitamin D are known as Calcifidiol and Calcitrol.

Vitamin D2 is found in fatty fish like salmon, tuna, sardines and mackerel. When your skin is exposed to UVB light from the sun it forms Vitamin D3.

As there are so few food sources of Vitamin D and too much sun exposure is a risky business as well, this vitamin is included in most multi-vitamins.

At the moment the RDA is still at only 200 IU for people under 50 and increases to 400 IU for 50 -70 year olds. However recent studies indicate that these levels are too low and should be increased significantly. See http://www.grassrootshealth.net/     for some interesting research results.

The important issue seems to be to have your serum level tested to establish if you need to have more or less Vitamin D.

Weak or painful bones are a result of Vitamin D deficiency. Some people's kidneys can't covert the vitamin and that leads to a deficiency as well.

Check out  this calculator to find out how much sunshine you need for your daily dose of Vitamin D.

Vitamin E

This is the body's protector against free radicals. It is one of the most effective antioxidant available in nature and is found in many different foods. One tablespoon of wheat germ oil covers the RDA of an adult (22.4 IU)comfortably, so do two to three ounces of almonds, sunflower seeds or hazelnuts.

Vitamin E deficiency is rare.

Vitamin K

Also know as Mendadiol - is the vitamin responsible for blood clotting. Deficiency is rare but can lead to excess bleeding.

Most of the vitamin K is actually produced in our gut. Green leafy vegetables, pea, beans, olives, soybeans, pears, plums and even meat and dairy products supplement the dietary intake.

Discuss any additional Vitamin K intake with your doctor or medical adviser. While on the one site Vitamin K helps to restore the gut flora after taking antibiotics for a while, a sudden increase in Vitamin K can interfere with the effects of blood thinning medication.