Here's a test for you. Can you eat only one cherry tomato and stop? What about one olive, or one cube of cheese? Many people would say yes. What about one square of chocolate? That's a different story-- once that sweetness hits your tastebuds, they're screaming out for more.

Our partiality for sugar seems to be biologically based, as tests with young babies have shown that they prefer sweet tastes to savoury, and breast milk has a natural sweetness. The problem is, as we grow older, keeping that liking under control, as sugar is one of the most addictive substances, and certainly the most addictive food.

An excessive amount of sugar affects the immune system in a variety of ways:

It greatly reduces the ability of the white blood cells to repel harmful bacteria for up to 5 hours after ingestion

It reduces the production of antibodies, which bind with and inactivate harmful bacteria

It interferes with the absorption of Vitamin C, an important nutrient for the healthy operation of the immune system

It causes an imbalance of minerals and even allergic reactions, which weaken the immune system

It nullifies the effects of essential fatty acids, inducing cells to be more permeable to invasion by

allergens and harmful bacteria

And as the effective functioning of your immune system is essential to your good health, it's easy to see how excessive sugar intake can have a significant impact on your well-being. It can raise your risk for a variety of ailments, from obesity and diabetes to heart disease, stroke and even cancer.

So what is an appropriate level of daily sugar consumption? The American Heart Foundation recommends an added sugar intake of no more than the equivalent of 6 teaspoons a day for women and 9 for men. Added sugar doesn't include sugar that is found naturally in dairy products and fruit-- these sugars are well tolerated and absorbed by the body as a result of the other vitamins, minerals and fibre incorporated in these foods.

Your added sugar intake can be difficult to measure, because as well as the usual suspects of cake, cookies, candy, chocolate and soda drinks, sugar is added to most processed foods, even bread and other products that don't taste sweet. To give you some idea, a normal 12 ounce can of Coke contains over 9 teaspoons of sugar, so if you're female and drink a can of Coke (or any soda) a day, you're already over the healthy level. High fructose corn syrup is a typical ingredient of many processed foods and is reported to be the main reason for the addictive character of so many fast foods.

Your body doesn't require sugars to function properly, and added sugars provide more calories and zero nutritional value to food. From a nutritional point of view, two pieces of fruit a day are quite sufficient provided that you're eating lots of other high fibre foods such as vegetables, nuts and seeds.

Some brave souls can go cold turkey on cutting out sugar, but for many it's a case of decreasing their intake progressively. Become an avid label-reader-- if a product has sugar in the first three ingredients, don't purchase it as the content will be high. Be aware that sugar takes many forms, so also look out for brown sugar, corn sweetener, corn syrup, fruit juice concentrate, high fructose corn syrup, honey, malt sugar, molasses, raw sugar, syrup and sugar molecules ending in 'ose' such as dextrose, maltose, sucrose etc

And while you're decreasing your use of sugar and improving your health, it's a good idea to take a probiotic supplement to strengthen your stores of good bacteria. to further increase your immunity and speed up the positive effect of your healthier eating.