Did granny know best?

In theory, eating a good diet couldn’t be simpler. Even granny knew the merits of fruit and vegetables, taking cod liver oil and ‘eating up your greens’.

In fact, there are only four key food groups which are needed in the diet to ensure we obtain all our nutrients. These are fruit and vegetables, whole grains (including nuts, seeds and beans), dairy products and oily fish. Unhappily, these foods are frequently neglected in a modern diet, which is why large sections of the UK population are not reaching their nutrient targets, as the latest UK National Diet and Nutrition Survey (NDNS)¹ shows only too well.

AN APPLE A DAY

The NDNS Survey found that the average intake of fruit and vegetables for men was 2.7 portions a day and 2.9 for women - much lower than the recommended target ‘five a day’. In fact, only 13% of men and 15% of women ate five portions a day. Among the 19 to 24-year-olds, the figures were even worse: none of the men and only 4% of women did so.

So why are nutritionists always so keen on fruit and vegetables? Is there any truth in the saying, ‘An apple a day keeps the doctor away?’ The answer is, ‘Yes!’ An apple provides a much needed boost to our fruit and vegetable intake; it supplies plenty of antioxidants, including vitamin C and plant chemicals (phytochemicals) such as the health-protective flavonoids and carotenoids. In addition, it contains fibre, B complex vitamins, some trace elements and potassium. Potassium has a diuretic action and is important for detoxification and reducing fluid retention. In fact, fruit and vegetables are almost unique in their high levels of antioxidants and potassium. So, with fewer than five a day, the intake of these nutrients can be exceedingly low.

GRANNY’S SCHOOL MILK

Milk is a good source of calcium, other minerals and certain vitamins. The NDNS Survey showed that over half of young women (19-24 years) had calcium intakes below the recommended target. Even in middle age, 40% of women had belowtarget intakes, as did about 30% of the elderly in a previous survey². For young women, low calcium intake is particularly worrying as it leads to reduced bone density and a greatly increased risk of osteoporosis in later life.

Dairy products are rich sources of calcium, unmatched by other foods, and, for a woman to reach her calcium target, she needs to have three portions of them a day. Granny’s school milk used to provide one of these. Despite a lot of misinformation to the contrary, significant amounts of calcium cannot be obtained from normal-sized portions of vegetables; their calcium content is far too low. Hence, it is essential that people abstaining from dairy products should supplement with calcium. The best calcium supplements also provide magnesium in the ratio of 2:1. This is important, as these two minerals interact and high levels of one can inhibit the absorption of the other.

GRANNY’S WHOLE GRAINS

Whole grains are seeds, cereals or beans with their coats included. The seed coat is very high in trace minerals, magnesium and B complex vitamins. Refining grains makes an enormous difference to their mineral content, a 20-fold drop in some cases. For example, manganese is a trace element with antioxidant properties needed for the formation of the enzyme, superoxide dismutase, part of the body’s defences against toxic free radicals. Refined cereals contain hardly any manganese, while it is high in whole grains. A similar scenario exists for another trace element, chromium, which is important for the utilisation of insulin and, therefore, for glucose control.

Although the NDNS Surveys do not report on trace elements, they do report on magnesium. The most recent survey showed that more people failed to reach their target for magnesium than for any other nutrient, reflecting their low intake of wholegrains. Often regarded as the ‘poor cousin’ among nutrients because its deficiency is not normally regarded as life-threatening, low status of magnesium in the body can substantially reduce quality of life. As with other nutrients, women’s intake is worse than that of men, with a massive 95% of women aged 19-24 years not reaching their target intake.

Magnesium has many roles - it is part of the structure of around 300 enzymes and is necessary for the formation of DNA and RNA. It is involved in energy production and fat and protein synthesis. It is also essential for proper muscle function, including that of the heart. Marginal deficiencies manifest as cramp, muscle twitching, palpitations, headaches, tightness across the chest and PMS. All these conditions are very prevalent among women today, but the remedy is easy: eat more whole grains or supplement with magnesium.

GRANNY’S BRAIN FOOD

Granny loved fish and believed it was good for the brain. Modern research shows this is true, mainly because of the fish oil, and a lot has been written on it in the media and Healthspan magazines. So comment is limited here. Suffice it to say that, in modern life, intakes of omega 6 fatty acids are high from manufactured food products, sunflower oil and margarine, whereas those of omega 3 oils from fish are low. This imbalance causes the body to become pro-inflammatory and prone to many chronic problems, including asthma, eczema, psoriasis, colitis, migraine and joint pain. The balance can be redressed by reducing an intake of omega 6 oils and the increasing intake of omega 3 fatty acids from oily fish or by taking an omega 3 rich supplement.

DID GRANNY TAKE SUPPLEMENTS?

Probably not and they cannot replace a good diet. In an ideal world, everyone should eat a healthy diet, but as the NDNS Survey shows, this is far from reality. If everyone took an A-Z multivitamin and mineral supplement every day as suggested in 2002 by Drs Fairfield and Fletcher in their article published in the Journal of the American Medical Association³, then no one would have an intake of micronutrients below their target levels. And everyone would enjoy the health benefit that the full nutrient repletion offers. But remember, an A-Z multivitamin does not provide enough calcium and magnesium, as the amounts required would make them too bulky for a single tablet. If you think you are lacking in these nutrients, then use a ‘bone formula’ containing calcium and magnesium, or a separate magnesium supplement.

CONCLUSION

The NDNS Survey has shown that many people, and especially women, are not reaching their targets for a wide range of vitamins and minerals. It is evident that this is because many are failing to eat healthily. While a good diet should always be the ultimate aim of nutritional advice, as granny advocated, a more pragmatic approach is needed if chronic disease is to be reduced. In granny’s day, good-quality supplements were unavailable. Now all that has changed. The universal use of a daily A-Z multivitamin supplement would ensure that everyone meets micronutrient targets to achieve good health and reduce the risk of chronic disease.

¹NDNS (2003): National Diet and Nutrition Survey. ² NDNS (1998): National Diet and Nutrition Survey. ³ Fairfield KM & Fletcher RH (2002), JAMA 287, 3116.