Exactly how important is the relationship between nutrition and health?

All of us would like to lead a full and healthy life. We can expect children to get the usual childhood ailments, and most adults will fall ill now and again. Some of us have disabilities and challenges of one kind or another, but we surely would like to avoid the really nasty diseases that could strike us – the cancers, heart attacks, strokes, and diabetes.

We all know, too, that nutrition and health are related. The best way to keep well is to eat well – to give our bodies the best nourishment we possibly can.

As our bodies develop and grow, so our nutritional needs change, but what does not change is this relationship between good nutrition and health.

Lifelong good health actually starts before conception! How can that be? Well, both the prospective mom and dad need to be in good health themselves to even get the process of life underway.

After conception, a healthy foetus depends on a healthy environment in which to thrive – and this means that the pregnant woman needs to pay special attention to her dietary needs as well as those of her developing child. The mother's nutrition has a direct impact on the nutrition and health of her baby.

For more details about the nutrition and health of a pregnant mother, go to our page on pregnancy.

Kids then have special needs of their own as they are growing and developing at a phenomenal rate.

For more on the nutrition and health of young children, go here.

The nutritional demands of teens are also special as they undergo massive hormonal changes as they mature into adulthood.

Adult men and women also have special health concerns and nutritional requirements of their own that need attention, and finally old age has demands and challenges of its own. Nutrition and health continue to go hand in hand thorughout the seven ages of man!

Men can follow this link for more guidance.

These different ‘ages of man’ will be considered separately, but to start with we will look at something that is common to all of us throughout our lives – nutrition for health as it relates to our cells.


Our cells are the basic building blocks of our bodies. The link between nutrition and health starts here. Our entire physical body is made up of cells, and there are millions and millions of them – in our brains, our muscles, our organs and so on.

And basically, if our cells are not in good condition, then things start to go wrong, from just feeling bit lethargic and off-colour to being stricken with a potentially fatal disease.

How cells work

Our cells work bit like the internal combustion engine in a motor car.

An engine takes in fuel that is mixed with air to provide oxygen so that it will burn. The fuel and oxygen mixture is ignited by a spark, and the resulting explosion yields the energy that powers the motor. It also gives off toxic gases that have to be taken out through the exhaust system.

The cell works in a very similar way.

* The fuel is provided by our nutrition - carbohydrates and fats in the food that we eat. The oxygen comes from the air that we breathe.

* In the cell, although we don’t have little explosions going on in our bodies, the fuel is in effect burnt at body temperature and so gives off energy. Enzymes are what makes this happen.

* This energy, called ATP, powers everything that we do – grow, develop, think, move, breathe and so on.

* And yes, like the engine, there is toxic waste that has to be got rid of. This includes carbon dioxide and ‘free radicals’. If the fuel-and-oxygen mixture can’t get in freely, both the engine and the cell lose power, and if the toxic waste can’t get out freely it causes problems. – the car stops and we get sick!

And of course, if our cells are not healthy and working properly to give us energy, then at best we feel a bit weary and at worst we get diseased and even die.

In and out the membrane

You can see that it is important that the nutrition must get into the cell and the free radicals must get out, both as freely as possible.

Now each cell is surrounded by a cell membrane, and this in-and-out flow of nutrition and waste goes through this membrane.

If the cell membrane blocks this flow then we will lose energy or get sick. Therefore the condition of this cell membrane is absolutely crucial to our health and wellbeing. It has to be permeable to let nutrition in and waste out.

To sum all this up: Just as a chain is as strong as its weakest link, so you could say that your body is as healthy as its weakest cell. To keep our cells fit we first have to look after the cell membrane.

Nutrition keeps the cell membrane healthy

The cell membrane is mostly made up of lipids and sterols. We won’t go too far into biological science at this point, but lipids and sterols are fat-soluble, naturally-occurring molecules.

Lipids and sterols are amongst the so-called essential nutrients. The word “essential” has a special meaning in health science. It means that our bodies don’t make these things; we have to get them through what we eat and drink – in other words, they must be part of our nutrition. This is a prime example of the link between nutrition and health.

So to feed the cell membrane we need to provide it with lipids and sterols, and the foods that provide this nutrition are the whole grain foods – foods like bread, cereals and pasta that are made from unrefined flours. Other sources include brown rice, corn, and oats.

The important thing is that these foodstuffs must be unrefined. The refining process actually removes most of the nutritional value of the grains.

Nutrition keeps the machinery of the cell healthy

Once inside the cell the fuel needs to be converted into energy. This mainly takes place in organelles called mitochondria.

And guess what: the mitochondria have a double membrane across which chemical reactions take place to produce ATP, the energy currency of the body.

Enzymes are also necessary to enable the cell to produce energy. One can compare them to the spark plugs in an engine. They enable the chemical reactions to take place at body temperature and at a suitable rate. Enzymes are proteins, so the diet needs to provide the amino acids that are required for them to be synthesized in the body. They also need vitamins and minerals to function properly – a basic example of the link between nutrition and health.

Nutrition Protects the Cell from Toxic Waste

It is the toxic waste or free radicals that damage the cell and endanger our health. The things that provide protection are antioxidants that we get through our nutrition.

Think of this: just as metal rusts, oily and fatty things exposed to the air will go rancid. The fat reacts with the oxygen in the air - a process called oxidization. Both rust and rancid fat are the result of oxidative damage.

The same can happen in our bodies – there is fat in our bodies and we use oxygen, so there is always the potential for oxidative damage. And, as we have seen, the cell membrane is largely made up of lipids and sterols, which are fatty molecules.

Actually, other important molecules within the cell are also subject to this kind of damage.

For example, our DNA can be damaged, and this can lead to tumours. But at present our interest is specifically in the membranes.

Of the foods that we normally eat, the things that provide the best antioxidant protection are fruits and vegetables.

You particularly need the flavonoids and carotenoids, Vitamin C and Vitamin E. The carotenoids and Vitamin E work in the oily parts of the cell, and the flavonoids and Vitamin C, which are water soluble, work in the watery parts. All are important antioxidants.

Not all fruits and vegetables have this strong antioxidant effect. For example, carotenoids come from the red, orange, yellow and green fruits and vegetables while the flavonoids come from the purple and dark green ones.

Ideally you should be getting a mix of these every day (5 to 9 servings a day, in fact) to get the full range of protection. There will be more information about these important antioxidants in another article.

By the way, many people say that a glass of red wine is good for you. The redness provides the clue to this – it’s the flavonoids in the wine that provide the benefit!

Summing it up: Keeping cells healthy with nutrition

Putting all this together, as a basis for keeping our cells healthy we need to feed our cells with the lipids and sterols from whole grains and protect our cells with the antioxidants from fruit and vegetables. The nutrition and health of each cell are inextricably linked.

It’s simple, but it’s not as easy as it looks!

Some difficulties

One problem with getting the right nutrition for our cells is our own food choices. We tend to like the sugary and fatty foods more than the ones that are good for us. For example, fizzy drinks and hamburgers are more popular than carrot juice and broccoli.

Another problem, and a big one, is that a lot of our regular food is not as nutritious as it used to be.

Let’s look at some examples.

Whole grain foods are basic to good nutrition and health because they are the source of the essential oils, but a lot of modern grain-based food is made from refined grains that do not have these oils.

Food manufacturers have found that removing the oils makes the milling process easier and also extends the shelf-life of the eventual product. That’s what makes sliced bread possible – in the old days bread would go moldy within hours of being sliced because of the oils it contained.

Fruit and vegetables provide the antioxidants that protect our cells, but the best ones are not always the popular ones. For example, potatoes are not rich in antioxidants; spinach and broccoli are.

Also, we should be eating at least 5 to 9 servings a day of a wide range of these things. Repeat, five to nine servings a day! That is far more than most of us get.

Using dietary supplements might be prudent

We understand the relationship between nutrition and health, but the fact is that it is virtually impossible for us to get the right amounts of whole grains, fruit and vegetables, and other essential nutrients in our ordinary diets to provide adequate nutrition for good health. That’s why the health scientists at Harvard University advise that we should add on at least a daily multivitamin supplement. Many people recommend a lot more.


We have been looking at healthy cells as the basis of wellness and good health throughout our lives. In summary:

* The basic building block of our bodies is the cell, and we have trillions of them.

* The basis of good health is keeping all those cells in good condition by feeding them properly, protecting them from damage, and repairing them when they are damaged.

And the basic minimum needs are:

* The lipids and sterols from unrefined whole grain foods to keep our cells membranes functioning properly, and

* Carotenoids, flavonoids and other antioxidants from plenty of the right fruits and vegetables to protect them, and

* A good multivitamin to supplement your intake of these nutrients to be sure that they are up to the right levels for effective energy production.

Those are the basics, but only the basics. You may want to explore the whole question of nutrition and health a lot further by looking at other articles that appear on this site.