All too often when we decide to address our weight issues by consulting with a doctor, we are told to “eat healthy and exercise”. The reality is that obesity is a growing problem in South Africa and while it may seem like common sense to know how to “eat healthy”, many of us are quite ignorant when it comes to personal nutrition. Eating healthy does not necessarily mean that you will lose weight. Limiting your portion size will also not guarantee weight loss and while exercise is essential, eating the right foods is an important consideration when structuring your weight management plan.
The two main considerations when considering a healthy eating plan for losing weight is :
- Calorie Count
- Glycaemic Index (Glycemic Index or GI)
Calorie Counting for Weight Loss
Calories or kilojoules are the measure of energy potential of food. The idea behind calorie counting is that if you eat sufficient calories for your daily activity, then you will not gain, nor lose weight. Of course, it is not as simple as this but monitoring your calorie intake will ensure that you are keeping track of your intake. Calorie counting is significantly more accurate than estimating and controlling portion sizes of your meals.
It is important to first establish what your calorie requirements are based on your body weight and daily activity. Consult with a dietitian to calculate your exact calorie needs and factor in any changes necessary for weight loss. Usually, an average 70kg adult female who is moderately active requires approximately 2,000 calories per day while a male of the same age and weight may require between 2,200 to 2,500 calories. If you are unable to consult with a dietitian, start counting your daily calories and monitor if you are gaining or losing weight. You can then alter your intake at a later stage.
In South Africa, most foods are measured by kiloJoules (kJ) so you can convert between kilojoules and calories by dividing the kilojoule figure by 4.184 to get a calorie equivalent. An adult female can reduce the daily calorie intake to 1,500 calories per day in order to assist with weight loss while an adult male could consider a daily calorie intake of 1,800 calories. Consuming less than 1,000 calories per day can be dangerous for an adult as it may trigger a hormonal response similar to those seen in starvation diets or even result in vitamin and mineral deficiencies.
Glycaemic Index and ‘Good’ or ‘Bad’ Carbs
There has been a lot of talk about GI or glycaemic index in the media. Glycaemic index is simply the measure of a food’s potential to affect the blood sugar levels. A high GI food will be quickly digested and ‘flood’ the blood with ‘sugars’. The body then secretes insulin forcing the body’s cells to take in glucose from the blood and triggering the liver to store excess glucose as glycogen. Any remaining glucose will be stored as fat.
Ideally, eating a diet of low GI foods will greatly assist with any weight management plan. Low GI foods are broken down slowly and blood sugar is maintained at a constant level which allows the body to use the glucose for its energy needs rather than storage. The glycaemic index of some high GI foods can also be altered by a high protein intake in the same meal or opting for high fibre starches. By far, the main intake of high GI foods is due to the starches in your diet and bread (white, brown or wholewheat), pasta, and maize meal are medium to high GI foods. Rice, low GI and rye bread or durum wheat pasta are low GI options and should replace any high GI starches.
A low GI diet coupled with a calorie restriction eating plan are the main aspects of any weight loss plan. If you plan to lose weight and want to alter your eating habits accordingly, it is important to understand both these concepts of fat metabolism. However, you should bear in mind that weight loss is not just a matter of calorie counting and dietary changes. Exercise will often make the difference between maintaining the weight loss or short term results followed by weight gain that is more than your previous body weight.