As with certain foods, high levels of nutrients can be dangerous. This is why when Quest Nutritionists are formulating food supplements care is taken to provide nutrients within safe limits. By following the directions on the label, it is not possible to overdose on a nutrient. However, when combining a number of supplements, it is important that the sum total of a nutrient does not exceed the safety guidelines.
Safety guidelines adopted by reputable supplement manufacturers in the UK are published in the recent report, "The Safe Use of Supplements Benefits Good Health", Council for Responsible Nutrition, March 1999.
|
Micronutrients
|
Long
Term
|
Short
Term
|
Unit
|
|
Vitamin A*
|
2300
|
7500
|
mg
|
|
Vitamin D
|
10(a)
|
50
|
mg
|
|
Vitamin E
|
800
|
>800(b)
|
mg
|
|
Beta Carotene
|
20
|
>20(b)
|
mg
|
|
Thiamin (B1)
|
100(b)
|
100(b)
|
mg
|
|
Riboflavin (B2)
|
200(b)
|
200(b)
|
mg
|
|
Nicotinamide (B3)
|
450
|
1500
|
mg
|
|
Nicotinic acid
|
150
|
500
|
mg
|
|
Pyridoxine (B6)
|
100
|
200
|
mg
|
|
Folic Acid
|
400
|
700
|
mg
|
|
Vitamin B12
|
3000(a)
|
3000(b)
|
mg
|
|
Biotin
|
2500(b)
|
2500(b)
|
mg
|
|
Pantothenic Acid (B5)
|
1000(b)
|
1000(b)
|
mg
|
|
Vitamin C
|
2000
|
3000(b)
|
mg
|
|
Calcium
|
1500
|
1900
|
mg
|
|
Phosphorus
|
1500
|
1500
|
mg
|
|
Magnesium
|
300
|
400
|
mg
|
|
Chromium
|
200
|
300(b)
|
mg
|
|
Copper
|
5
|
8
|
mg
|
|
Iodine
|
500
|
700(b)
|
mg
|
|
Iron
|
15
|
80
|
mg
|
|
Manganese
|
15
|
20(b)
|
mg
|
|
Molybdenum
|
200
|
10000
|
mg
|
|
Selenium
|
200
|
700
|
mg
|
|
Zinc
|
15
|
50(c)
|
mg
|
|
