Sugar has always been a controversial issue with most health-conscious athletes. We are constantly bombarded with info about how sugar can cause holes in our teeth, affect our mood and energy levels, make us fat and cause illnesses such as diabetes and cancer. But let’s face it, sugar is a key nutrient in sport and without it our diets would be very bland. Nutritionists agree that sugar has a place in a healthy diet, as long as it is balanced in amount, type and timing. – BY CHRISTINE PETERS
SUGAR: A CARBOHYDRATE
There are three so-called macronutrients in our diets: proteins, fats and carbohydrates. Carbohydrates and fats supply the body with the energy vital for existence. Sugars, along with starches and dietary fibres, fall into the carbohydrate group. Plant foods, such as cereals and grains (maize, wheat, rice) and fruits and vegetables, are the primary sources of carbohydrates in the diet. Plant carbohydrates vary widely in sweetness, texture, rate of digestion, and degree to which they are absorbed in the body.
Carbohydrates can be categorised as:
• Monosaccharides (glucose, fructose and galactose)
• Disaccharides and oligosaccharides (sucrose such as table sugar, lactose or milk sugar, and maltose)
• Polysaccharides (starch and fibres)
The prefix ‘mono’ refers to one sugar, ‘di’ indicates that two sugars are combined, and ‘poly’ indicates the combination of many sugars.
All carbohydrates are eventually broken down into the simple sugars (mono and disaccharides) and absorbed into the bloodstream. Because glucose, fructose and galactose are absorbed at different rates and have different metabolic pathways, the type of carbohydrate influences the effect it has on the blood sugar levels. Simple carbs can occur naturally within a food e.g. fructose in fruit, or they can be added to a food (added sugars).
Because processed foods containing added sugars are replacing other foods in the South African diet, simple carbs have increased significantly as compared to more complex starches or fibres. It is these added sugars that are to blame for the increase in obesity.
HOW MUCH IS TOO MUCH?
When eaten, sugar is rapidly absorbed into the bloodstream, causing a surge in the hormone insulin. Insulin clears sugar and fat from the bloodstream, and enables them to be stored in tissue for future use. Go overboard with added sugar and eventually your body’s insulin system will stop working, leaving you with high blood sugar and eventually, diabetes and other illnesses. The World Health Organization recommends limiting your sugar intake to 10% of your total daily calories. So if you eat 2 500 calories, 250 of them can be from added sugar. One of the biggest mistakes we make is overloading our bodies with sugar during an event. This leads to a slower digestive system and your blunted insulin levels during exercise, which means that we can process only so much food and pull only so much glucose into our cells.
During exercise the body can process 30-60 grams of carbs per hour. Consume too much energy and you’ll not only take in too many calories, you are also likely to suffer from gastrointestinal disturbances. Use the following guidelines to ensure you take in the correct amount of sugar:
• For activities less than 60min a day, you can get away with avoiding simple carbs (bars, gels, sports drinks) and focusing more on adding complex carbs to your normal diet.
• If you train more than 90min a day, you will need to replenish your muscles during and after an event. The general rule is 30-60g of carbs per 45-60min or 8-10km, whichever comes first.
HOW TO CHOOSE YOUR SUGAR
Sugars in energy products come in different forms: glucose, fructose, sucrose and maltodextrin. For the best performance benefits, use products with a blend of sugars. Various studies have found that when trained athletes consume drinks with mixed sugars, they are able to process, digest and absorb considerably more carbs per minute than when they drink single-sugar energy drinks.
It comes down to what you like and what your body can tolerate while you run. Genetically, we all have different abilities to digest and absorb various carbohydrates. Digestion becomes slower the faster you go. Play around with different products and figure out what works for you. Don’t overdo it on the sugar. All the carbs in the world will do you no good if you can’t get them out of your gut and into your legs.
The following table details exactly how much sugar is in the typical foods we eat, and which healthy alternatives we can substitute them with.
Example of high sugar food Healthier alternative
Milk chocolate bar 22g sugar; Cereal bar 14g sugar; 9g sugar Cooked oats (3/4 cup); 0.4g sugar Commercial large muffin; 36g sugar Oat bran muffin (homestyle); 14g sugar Coke (one cup); 27g sugar Low fat milk (one cup); 14g sugar Low fat fruit yoghurt (one cup); 46g sugar Low fat plain yoghurt (one cup).
Note: 15g of sugar or carbohydrate is equivalent to one slice of bread in terms of portion size.
INTERESTING FACTS ABOUT SUGAR
• ‘Low sugar’ is supposed to mean less than 5g of sugar per 100g of food.
• Often fat free products have more added sugar to make up for taste and to act as a filler.
• Honey is very similar in terms of calories/energy to table sugar, but does have other health benefits if not used in excess.
• Xylitol is a great alternative to sugar for those trying to lose weight, have diabetes or are prone to dental problems.