Some People DO Need Vitamin Supplements

You may have heard some recent sweeping claims that everyone can get all the vitamins and minerals they need from their diet, and that multivitamins are a waste of time and money. If only this were true. The UK National Diet and Nutrition Surveys clearly show that significant numbers of adults and children obtain less than the minimum level that is needed to prevent nutritional deficiency diseases.

Reference nutrient intakes (RNIs)

Reference Nutrient Intakes (RNIs) are designed to meet the needs of 97.5% of the population. These amounts are calculated statistically, for each vitamin and mineral, from the estimated average requirement which meets the needs of 50% of the population. Around one in two people will need more than this level, and one in two will need less.

The important cut-off on which to focus is the lower reference nutrient intake (LRNI) which only meets the needs of an estimated 2.5% of the population. Most of us (97.5%) will need more than this minimal intake.

LRNI_standard_distribution

Anyone who consistently obtains less than the Lower Reference Nutrient Intake (LRNI) for any vitamin or mineral is likely to develop symptoms of deficiency as only 2.5% of people can get by with less than this amount.

You might think that few people are at risk of deficiency diseases in a country like the UK, where over-nutrition and obesity are growing problems. In fact, the National Diet and Nutrition Surveys clearly show that nutrient intakes are low for significant sections of the population. These low intakes are disguised by the average intakes, however.

Average intakes may seem OK …

As you can see for adult men and women in the chart below, the average female intake of iron, magnesium, potassium and selenium is below the RNI. For men, average intakes do not meet the RNI for magnesium, potassium or selenium.

NDNS1

Average intakes for vitamin A, vitamin C, folate and for the minerals calcium, iodine and zinc may seem acceptable – if not good – but an average is only an average. Some are getting more while others get significantly less. A worrying number of people do not even obtain the Lower RNI (LRNI) that only meets the needs of 2.5% of the population.

NDNS2

More than one in 10 men get less than the LRNI for vitamin A.

Over 1 in 10 adults get less than the LRNI for magnesium, potassium and selenium.

Nearly 25% of women have a low iron intake.

These low intakes are associated with nutritional deficiency diseases if sustained over a period of time and, in fact, 5% of older girls and adult women have iron-deficiency anaemia. Intakes are particularly worrying for adolescent girls, who need good intakes of vitamins and minerals to support optimal growth.

NDNS3

Almost one in two girls (46%) have worryingly low iron intakes, and over one in two are not getting enough magnesium.

Intakes below the LRNI were also found for folate and riboflavin (vitamin B2).

When it comes to vitamin D deficiency, blood tests showed evidence of low vitamin D status in 23% of adults aged 19 to 64 years and 22% children aged 11 to 18 years over the year as a whole. This increased to 40% for both in the winter months.

Not everyone gets all the nutrition they need from their food

To blithely say that we can get all the vitamins and minerals we need from our food, without checking the facts, is a misrepresentation of what actually happens in reality.

Diet should always come first, but if you are cutting back on food intake to lose weight, avoiding certain foods because of intolerances, skip meals because of a busy lifestyle, or simply have a poor appetite, then a multivitamin and mineral supplement acts as a nutritional safety net. Select one that supplies a sensible dose (around 100% of the recommended daily amount, or RDA, for as many micronutrients as possible) and avoid megadoses.

Click here to read my Expert Health Review of Multivitamin brands.