There is no such thing as a good diet for everyone. Nutrionist Margaret Moss explains why.


We can’t survive without food. It provides us with fats, carbohydrates and protein for energy; proteins and fats for our cell membranes and immunity; protein for muscle, hormones and enzymes; minerals for reading our DNA; and vitamins to work with minerals and proteins to make the whole system work.

So, if food is so vital for us, why does it make so many of us ill, and often kill us?

We aren’t the centre of the universe. Like other beings, we eat what we can find. Food isn’t designed for us to eat. Seeds are for making new plants. Leaves are for obtaining solar energy. Fruits are for birds to eat, so that they spread the seeds. Animals are born to keep their species going. What is available depends on the climate where we live. Whether we consume a lot of milk, fish, meat, wheat, rice, cabbages or mangoes depends on where we live. Some are lucky to live where healthier foods grow.

Our ancestors learnt slowly from experience that some foods would make us drop dead. In India, when other crops fail, people fall back on chickpeas, a vetch that contains a nerve poison. Outbreaks of paralysis are connected with this famine crop, but it does keep people alive when there is nothing else. People also learnt that some foods were helpful. Kenyan villagers learnt that finger millet porridge helped mothers make milk for their babies. We now know that finger millet is a good source of calcium. Why don’t we import it? In India, those who could afford lentils as well as rice throve, as did those in Africa who could afford beans as well as maize.

Where consequences are rapid, we learn.

Where consequences are rapid, we learn. It is easy to discover that deadly nightshade kills people. It is easy to see that eating peanuts caused Jimmy to develop a rapid anaphylactic shock, because of his high levels of IgE antibodies to peanut. It is much harder to realise that the milk Vanessa has on her cornflakes every day causes her asthma symptoms, or that the same milk will give Desmond a heart attack. It isn’t obvious that the sweets that Susan loves are feeding her breast cancer.

From necessity to pleasure

Life has changed greatly in the last two centuries. People moved from the potatoes and cabbages of the countryside to the bread and margarine of the cities. Corner shops sold foods that didn’t go off. Foods that bacteria don’t like are often not very good for us either. Then came the advertising era. Eating was no longer to give you health and strength. It became a fun activity. Sugars appeal to a sweet tooth, and it isn’t immediately clear that they contribute to type two diabetes, obesity, irritable bowel syndrome and tumour growth.

Some British researchers, like Cleave and Yudkin, realised how harmful sugars are. However the Americans decided to blame fats for ill health. They had the money and  the power. People were persuaded to cut their fat intake. Fats make food attractive. Fat-free food was boring. So sugars and additives were added, and obesity and diabetes soared.

Sugar, sugar and sugar...

Glucose, sucrose, fructose and galactose are sugars, but enzymes end in –ase. Sugars  attach to protein, making nasty chemicals, a process known as glycation. Cholesterol is needed to make hormones and vitamin D. However sugars attach to cholesterol, and then it becomes oxidised, and dumped in artery walls. This led to Desmond’s heart attack. Milk sugar is called lactose. Babies and northern people usually have an enzyme called lactase, which breaks lactose into glucose and galactose. Galactose is a particularly vicious glycator. If you are short of lactase, like many equatorial people, undigested lactose is not absorbed, and feeds bacteria in the gut, making you uncomfortable. You do not have a lot of galactose, and your arteries are protected. So don’t buy the enzyme lactase, to break down milk sugar. That will threaten your arteries. Again. Don’t buy milk already treated with lactase.

A very small proportion of people have galactosaemia. For them galactose is very toxic.

The sugar we obtain from sugar beet and sugar cane is called sucrose. The enzyme sucrase splits sucrose into glucose and fructose. Fructose is also in fruit. Fructose is a strong glycator, although not as vicious as galactose. We are limited in our ability to absorb fructose. What we do not absorb feeds harmful organisms in the gut, causing discomfort and diarrhoea. Some people have fructose malabsorption, and tolerate little fructose. Others have normal absorption, but consuming a lot of fruit, fruit juice and sugar exceeds their capacity to absorb it. They can end up with IBS too. A more serious but less common condition is fructose intolerance, an inability to process the fructose that has been absorbed. Paediatricians sometimes identify this, but adult physicians rarely do. They do not realise that today’s pensioners were born before such conditions were known. Fructose is harmful to diabetics, and it is a mistake for them only to worry about glucose. High fructose corn syrup is also harmful.

Glucose is obtained by breaking down starches, lactose and sucrose. Glucose is a less potent glycator than fructose or galactose, but those who have high glucose levels will suffer from glycation. The glycaemic index diet is good, because it cuts down consumption of beet and cane sugar. However, it is bad, in that it persuades people to replace glucose by fructose, which is worse.

Over-exposure can build up food sensitivity.

Over-exposure can build up food sensitivity. Bread and milk are common in the British diet, and sensitivity to them is common here. Maize is a common food in the Southern USA, and a lot of people there are sensitive to it. Sesame is a common problem in Israel, and Swifts’ nest soup in China. If you are ill on your current diet, change to a different way of eating. The anorexic vegetarian may recover on eating meat and fish, which provide zinc and omega three fats. The meat eater with ulcerative colitis may recover by going vegetarian. The constipated consumer of a low roughage diet may need fibre from golden linseeds or figs, while the wholemeal consuming arthritic may do better on refined grains, or none at all. One person’s meat is another’s poison. There is no such thing as a good diet for everyone.

Inflammation is bad...

The immune system needs to be finely balanced. We must be able to produce inflammation to kill off harmful micro-organisms. We should not be inflamed all the time, like someone with rheumatoid arthritis. A baby has an immune system that tends to allergic mode. Infections, especially parasitic ones, switch the baby’s immune system to the adult mode, which fights infection. Parasitic infections can be debilitating. However, a low dose of parasites switches people away from allergy. This treatment is still experimental, but may be more easily available in the future.

Vitamin D is good...

Vitamin D calms the immune system. Exposure to too much harsh sunlight can cause skin cancers, especially in fair skinned people. Likewise, Western cattle imported into Africa can suffer from cancer of the vulva. However, vitamin D is an important tool for combating allergy, multiple sclerosis, depression, heart disease, osteoporosis and cancer. Some exposure to mild sunlight is valuable. If this is inadequate, vitamin D supplements are essential.

Fats – but which fats?

Fats are long chains of carbon atoms, with other atoms attached to them. Omega six fats are essential. They are found in nuts and seeds, as well as in the oil made from these. They are needed for the immune system to fight infection. They need to be balanced by long chain omega three fats from fish. Those who do not have fish or fish oil can obtain shorter chain omega three fats from flax oil. These have to be processed in the body. If vitamins and minerals are inadequate, or if there are gene defects, this will not take place sufficiently. If you are buying fish oil, choose the oil from the flesh of oily fish, not from the liver. If fish swim in contaminated seas, the liver will be particularly contaminated. Moreover, some people become very ill if they take too much vitamin A. Liver oil contains this.

Nowadays babies are tested for phenylketonuria, a condition causing intolerance of part of protein. It they consume it, it damages their brains.

Why food makes people ill is a very individual matter.

Why food makes people ill is a very individual matter.  It would be lovely to have a reliable test that told you what is good for you. However, no one test can identify all the possible triggers of illness.

When a murder takes place, the detectives cannot simply “run the murder test”, to find out who did it. They have to collect the evidence in a painstaking way, and sift it for clues.

Sorting out food-induced illness cannot be done by just “doing the intolerance test.” There are different tests for different conditions, like IgE mediated allergies, leaky gut, lactose intolerance, fructose intolerance, vitamin A levels, phenylketonuria and coeliac disease.


Margaret Moss MA UCTD DipION CBiol MSB MBANT
CNHC Registered Nutritional Therapist
11 Mauldeth Close, Stockport. Cheshire.
0161 432 0964.


First published in March 2012

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