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September 6, 2014

Vitamin dosage and toxicicty

by Helene van den Berg


Are vitamins in large doses harmful?

Isolated vitamins of the B-complex can be harmful and vitamins A and D. These vitamins should not be taken in synthetic form in LARGE doses without expert professional advice. There is no risk involved if they are taken in the form of brewer’s yeast (for B-vitamins) and unfortified fish liver oils (vit A and D).

It is the wisest and safest to take vitamins and minerals in their natural form and strength and in combination with enzymes and trace elements, for optimum assimilation.


The classic concept by doctors are that vitamins (supplements/vitamin-rich foods) should be used only in correcting vitamin deficiencies – and then only in minimal daily requirements (MDR). The classic concept of vitamin use is that, when health disorders are caused by vitamin deficiencies, prescribed vitamins will correct the deficiency and combat the disorder.

The new concept of vitamin therapy are now used in HUGE DOSES, FAR ABOVE THE NUTRITIONAL NEEDS. In large doses, many vitamins have a miraculous healing, stimulating and protective effect on the various body functions, an effect that is totally different from the usual vitamin activity as nutritional catalysts e.g. you need only 100-200 mg/day of vitamin C for normal, healthy functions of the body, BUT when you take huge doses like 3000 mg/day, it will do miraculous things as, neutralizing various toxins and poisons, help to oxygenate the tissues, heal wounds etc. OR with vitamin E, taken in large doses of 600-1000 IU/day, assumes a drug-like role and performs a completely different activity.


The general rule is to take supplements with food – reason being that stomach acid helps many minerals to be absorbed and fat-soluble vitamins are carried by fat/oils present in most meals.

Nutrients do, however, compete for absorption e.g. amino acid, lysine (good for arteries and prevent herpes), is better absorbed on an empty stomach or with non-protein foods, like fruit. Selenium is better absorbed on it’s own, than as part of a multimineral. The best advice is to spread your nutrients out through the day and take them with meals EXCEPT with “ascorbic acid” type (weak acid) of Vitamin C, taken in large doses of 3000 mg/day – take it away from meals to avoid neutralizing the acidity in your stomach. If you experience a burning sensation after taking ascorbic acid, you need to see your doctor to check for an ulcer/gastro-intestinal irritation.


Thiamine (B1)

  • The body contains 25mg
  • RDA is 1.2 mg/day
  • Therapeutic dose is 10-100 mg/day
  • Non-toxic

Riboflavin (B2)

  • RDA is 1.7mg
  • Therapeutic dose is 10-100 mg/day
  • Non-toxic
Niacin (B3)
  • RDA is 20mg
  • Therapeutic dose is 50-3000 mg/day
  • Non-toxic (transient flush above 75mg)
  • High doses can cause hot flushes, itchy for up to 30 min – it will improve with regular supplementation or take ½ dose 2x/day. Use “no flush” type; nausea and vomiting

Pantothenic acid (B5)

  • RDA is 10mg
  • Therapeutic dose is 50-300 mg/day
  • Non-toxic
Pyridoxine (B6)
  • RDA is 2mg
  • Therapeutic dose is 50-500 mg/day
  • Toxic dose is over 500 mg/day
  • Symptoms of overdose include depression, fatigue, headaches; nerve damage (inability to walk & convulsions); skin lesions


  • RDA is 0.3 mg
  • Therapeutic dose is up to 0.3 mg
  • Non-toxic

Folic acid (B9)

  • RDA is 0.4 mg (400µg/day)
  • Therapeutic dose is 0.8 – 5 mg/day
  • Non-toxic
  • High levels may masks Vit B12 – deficiency symptoms
Cobalamin (B12)
  • The body contains 5 mg
  • RDA is 0.006 mg (6µg/day)
  • Therapeutic dose is 0.05 to 1.0 mg/day
  • Non-toxic

Vit C

  • The body contains 1400 mg
  • RDA is 60 mg/day
  • Therapeutic dose is 100-100 000 mg/day or more
  • Non-toxic, (diarrhea above bowel tolerance = varies) more than 25 000 IU long term can cause symptomes of toxicity
  • Symptomes of toxicity includes kidney stones, urinary tract problems, aggravate gout symptoms, nausea, abdominal cramps, diarrhea, insomnia, hot flashes, rashes.

Vit A (retinol)

  • (Beta-carotene is non-toxic at all doses, but skin go yellow)
  • The body contains 500 000 IU
  • RDA is (172mg) or 5 000 IU/day
  • Therapeutic dose is 50 000 – 500 000 IU/day in short term
  • Toxic dose is more than 100 000 IU/day long term
  • Chronic toxity symptoms include birth defects; liver abnormalities; reduced bone mineral density
  • Acute toxity symptoms include blurred vision; nausea , vomiting; headaches; vertigo

Vit D

  • RDA is 400 IU/ day
  • Therapeutic dose is 500 – 5000 IU/day
  • Non-toxic, however can be detrimental in rheumatic heart disease – limit to 200 IU in these patients
  • Sympyoms of overdose include elevated blood calcium; calcification of soft tissues ( blood vessels, heart, kidneys, lungs, tissues around joints)
Vit E
  • RDA is 30 IU/day
  • Therapeutic dose is 50-1600 IU/day
  • Toxic dose is over 0.5 mg/day
  • At high doses it can augments the effect of anticlotting medication

Vit K

  • RDA is 60-120 µg/day (Sufficient produced by bowel bacteria)
  • Therapeutic dose is up to 0.3 mg/day



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