Live longer, live better - eat less

The energy we get from the food consumed is expressed in units called calories. Different foods have different caloric values. While proteins and carbohydrates supply four calories per gram (gm), fats provide over twice that amount - nine calories per gm. So the quantity of calories you consume depends not only on how much food, but also on the type of food that you eat. Alcohol is not a food but provides seven calories per gm.

This common custom of over-consumption of food has dire consequences to health, even among those who may appear healthy. Simply eating and drinking too much can make you sick or even kill you. Medical research shows it results in a greatly increased risk of developing common disorders like diabetes, hypertension, lipid (cholesterol and triglycerides) disorders, heart disease and strokes.

CALORIE RESTRICTION (CR)

Research has consistently demonstrated that when you restrict the amount of calories an animal eats while making sure it gets all the nourishment it needs, a process called calorie restriction (CR), then the animal lives a longer and healthier life. CR not only extends the lifespan of laboratory animals but also reduces the incidence of virtually all diseases of ageing, such as cancer, heart disease, diabetes, osteoporosis, auto-immune disorders, neurological decline and conditions like Alzheimer's and Parkinson's disease. In some cases, the lifespan of animals in the laboratory has been doubled. This is the only strategy that has been proven to extend the average and maximum lifespan of animals.

CR - From Mice to Men

The big question is: is CR applicable to humans? For many practical reasons the research has not been conducted in humans but there is compelling evidence that keeping your body weight low (one result of CR) can make you live longer.

In 1997, a study on body weight and mortality in the American Journal of Clinical Nutrition stated: "We conclude that when appropriate adjustments are made for effects of smoking and underlying disease, the optimal weights for longevity are below average in both men and women." In other words, a healthy person with low body weight lives longer that a healthy person with a high body weight.

Challenges with CR

A serious calorie restriction diet aims to reduce your intake of calories to a level 20-40 per cent lower than is typical, while still obtaining all the necessary nutrients and vitamins. The average person is challenged to make such a drastic change in their diet: hunger, a lack of discipline and information and prevailing social norms are major obstacles.

A PRACTICAL APPROACH TO CR

Change your mindset: Most people have been programmed to think that more is always better. With respect to food and optimal health, less is often better. Begin with small adjustments to your diet.

Use modern food technology: Food science has created meal-replacement drinks called shakes that can provide all the nutrients you would get in a large balanced meal while greatly restricting your calorie intake. There are lots of shakes on the market and some people create their own, but not all are equal. Choose carefully. You need a nutrient dense and low calorie shake. For over 17 years I have replaced one or more of my meals each day with a shake from Herbalife International. It provides lots of all the key nutrients for less than 200 calories. The shake is an economical, delicious and convenient way to embark on CR.

Focus on water-rich, high-fibre foods: Since water contains no calories, and fibre is the non-digestible part of plant foods, foods high in water and fibre will tend to be lower in caloric content. They also add volume and bulk to the food, thus creating a greater feeling of fullness and satiety. Fresh fruits and vegetables should therefore be a big part of your meal plan. Remember, however, that very sweet fruit like mangoes and ripe bananas provide lots of sugar and calories and can sabotage your CR programme.

Cut back on fats and alcohol: As indicated earlier, fats and alcohol have a very high caloric content and their consumption should be restricted. Healthy fats like the omega-3 fatty acids are, however, essential.

Ease up on sugar and starch: Although these carbohydrates have lower calories, we easily consume too much of them as they create cravings for more. Cut back significantly on these foods.

Have enough protein: While proteins are low in calories, they provide the materials for the body to repair and renew itself. Do not skimp on healthy protein foods. One important feature of the shake I referred to is that it is an excellent source of protein.

You may email Dr Tony Vendryes at vendryes@mac.com or listen to 'An Ounce of Prevention' on Power 106FM on Fridays at 8 p.m. The programme streams live on the Internet.