There are many reasons why being overweight is bad for your health. It can, for example, cause or aggravate type 2 diabetes. Obesity is also a risk factor for heart disease and other cardiovascular problems.
So what do you have to do to lose weight?
Eat less and move more is the trite answer that someone who is overweight usually receives.
Of course, you can lose weight by reducing the amount of food you eat (energy intake) or by increasing the amount of exercise you do (energy output).
But the problem of effective weight loss is much more complex than simply changing the balance between the calories you consume and those you expend in your daily activities.
The search for an effective weight loss formula requires answers to these four questions:
- Do genetics play a role in your weight problems, and if so, what can you do about it?
- How many calories do you need to cut out of your diet to lose a pound or a kilo?
- What are the best types of foods (carbohydrates, fats or proteins) to lose weight?
- Is exercise very good at helping you lose weight or keep it off?
How genes affect your weight
Many people try their best to lose weight without much success. In particular, once they’ve lost a few pounds, they find it extremely difficult to keep the weight down…it just comes right back on.
This suggests that the problem is genetic.
In fact, more than 30 genes have been linked to obesity. The one with the strongest link is the gene associated with fat mass and obesity (FTO).
The obesity risk variant of the FTO gene affects one in six of the population. Studies suggest that people who have this gene are 70% more likely to become obese.
According to research published in the UK in 2013 in the Clinical Research Journal, people with this gene have higher levels of ghrelin, the hunger hormone, in their blood. This means that they begin to feel hungry again shortly after eating.
In addition, real-time brain imaging shows that the FTO gene variation changes how the brain responds to ghrelin and food images in brain regions linked to feeding and reward control.
These findings explain why people with the obesity-risk variant of the FTO gene eat more and prefer higher-calorie foods…even before they become overweight…compared to those with the low-risk version of the gene.
The FTO gene is not the only genetic cause of obesity, which is probably due to the sum of several genes working together.
However, if you have these ‘bad’ genes, you’re not necessarily destined to be overweight… but you’re more likely to end up obese if you overeat.
Having these genes also means you’ll need to exercise more discipline over your diet throughout your life, especially when you’ve managed to shed a few pounds and want to keep them off.
How many calories should you cut down to lose weight?
The big question for dieters has always been… how many calories do I need to cut out of my diet to reduce my weight by a certain amount, say a pound or a kilo?
Once upon a time there was a clear answer to this question.
In 1958, Max Wishnofsky, a New York physician, wrote an article that summarized everything that was known at the time about how calories are stored in our bodies. He concluded that if his weight remained stable, a deficit of 3,500 calories would be needed to lose one pound (454 grams) of weight.
You can create the calorie deficit by eating less or exercising more (to consume more calories).
For example, if your weight remains stable on a 2,000 calorie per day diet and you reduce your intake to 1,500 calories per day, you will lose one pound in a week, or 52 pounds or 24 kg per year. .
Alternatively, you could burn an extra 500 calories a day (through exercise) to lose the same amount of weight over the same time periods.
For years, Wishnofsky’s rule was accepted as verified fact. It is the basis of a wide variety of diets.
The only problem is that the rule is wrong. It does not take into account the changes in metabolism that occur when following a weight loss diet.
Wishnofsky’s rule actually works initially. But after a week or two, your weight bottoms out, much to the frustration of thousands of dieters as your metabolism adjusts to your declining body mass and reduced food intake.
Until recently, there was no way to predict how consuming fewer calories affects the rate at which you’ll lose weight, especially when your goal is to lose more than a few pounds or kilograms.
However, there are now complex new weight loss formulas that take into account the drop in metabolic rate that occurs over time as body mass decreases. An example is the body weight planner of the National Institute of Diabetes and Kidney and Digestive Diseases of the United States.
What types of foods should you cut out to lose weight?
What types of foods should you cut out to lose weight?
Should you cut calories from your fat, carbohydrate, or protein intake? Which will help you lose weight faster?
The number of calories in a gram of each of the basic types of food is as follows:
Fat…9 calories per gram
Drinking alcohol… 7 calories per gram
Protein…4 calories per gram
Carbohydrates… 4 calories per gram
Dietary fiber… 2 calories per gram
Since fat contains more than twice as many calories as carbohydrates and protein, cutting back on the fat you eat will work twice as fast as cutting down on either of the other two types of food, gram for gram.
This is why diets that focus on reducing the fat you eat, such as diet to beat diabetes and the Mediterranean diet They are effective in reducing weight.
But if you want to reduce your calorie intake by a fixed amount per day (say 500 calories), will it make a difference in what kinds of foods you should cut back on?
For example, will there be any difference in the amount of weight you lose if you remove 55.6 grams of fat (500 calories) or 125 g of carbohydrates (500 calories) or 125 g of protein (500 calories) from your diet?
The answer is that there is little difference in the amount of weight people lose if they cut calories from carbohydrates or fat.
But calories from protein are different…according to researchers, high-protein diets tend to increase the number of calories you burn. Why this is so is not clear.
However, when people lose weight, they lose both muscle and fat. The more muscle you lose, the more your metabolism slows down, slowing down the rate at which you lose weight.
Because it preserves muscle, a protein-based diet can slow the rate at which metabolism slows.
The problem is that if you eat too much protein, you could end up damaging your kidneys. The generally accepted recommendation is that you limit your protein intake to a maximum of 35% of your total daily calorie intake.
So, as long as you’re not eating too much protein, it’s best to reduce weight by cutting back on fat (for your heart’s sake, etc.) and refined carbohydrates that raise blood glucose levels (especially if you have diabetes).
Does exercise help you lose weight or keep it off?
Reducing food intake is the best way to lose weight. Exercise is less important, at least in the initial stages.
Exercising when you’re trying to lose weight can be tricky. You burn calories for sure, but not as many as if you didn’t eat those calories in the first place.
And exercise increases your appetite, so it’s easy to make up for all the calories you burn during an intense workout.
The recommendation, when you’re cutting back on your food intake to lose weight, is to focus on moderate physical activities like gardening or brisk walking, rather than hitting the gym.
But once you’ve shed those extra pounds and are at your ideal weight, exercise becomes important to keep your weight at its new, healthier level.
Researchers have found that most people who lose weight and manage to keep it off for at least a year exercise regularly for up to an hour a day.