A Calorie is Not Just a Calorie – The Calorie Counting Approach to Weight Loss Does Not Work Long Time.

There is an advert for Weight Watchers on television at the moment that states that their approach to weight loss is ‘not rocket science’.  Unfortunately, nutrition and the human body is however Human Science and therefore although you may find results in the short time with Weight Watchers, give it a year and you will be putting the weight back on.

Is it worth it?  Is eating a packet of low fat crisps or cutting a slice of low fat cake really healthy and is it really the way you envisage spending the rest of your life?

Food Calories affect the body very differently depending on their source and the overall context in which they are consumed.

Simply put a calorie-based weight loss system doesn’t work for two principle reasons:

1. Carbs, Proteins, and fats produce different hormone responses that directly influence the metabolic rate and whether the body is in a fat burning or storing mode.

• Calorie restriction slows metabolism – if you restrict your diet excessively (more than 500 calorie deficit) you may well find you lose weight in the first few weeks, but then in subsequent weeks this slows down or stops.  Your body literally runs cooler to conserve the reduced number of calories you’re eating, thereby effectively increasing the value of each calorie.  This phenomenon is believed to represent a metabolic adaptation to prevent starvation.
• In a study published in the Journal of the American Medical Association, people who matched their calories intake with their calorie needs throughout the day were leaner than those who tended to fall behind.
• It is also important to note the timing of eating should be spread evenly throughout the day – 6 small meals totalling 2500 calories are not equal to 2 large meals totalling 2500.  Food calories are more likely to be stored as fat when they are consumed in excess of our short-term needs.  We tend to burn more calories in the morning than in the evening.

2. The amount of calories required for the body to break down different foods varies greatly.  Your body will burn significantly more calories digesting a meal of animal protein and fibrous leafy greens than a meal of carbs such as pasta with tomato sauce.  Fats and processed foods such as biscuits, white bread and crisps require even fewer calories to be digested and absorbed.

• Protein reduces appetite – increasing protein intake is likely to lead to a reduced total calorie intake due to a reduced appetite.
• Fibre reduces calories absorption – Fibre is a form of carbohydrate that contributes to satiety without contributing calories, because it is not absorbed by the body.  Thus a calorie inside a high fibre food is not equal to a calorie inside a low fibre food.

Important Facts of Science to Remember:

1. A protein calorie is NOT the same as a carbohydrate calorie or a fat calorie

2. The Thermic Effect (energy used to digest and absorb a meal) of different macronutrients varies just as it does with processed foods compared to whole foods

3. Macronutrient ratios will determine hormone response – a calories-restricted diet can elevate levels of hormones ghrelin, which stimulate hunger, and gastric inhibitory polypeptide, which promotes fat storage.  Leptin, a hormone that suppresses hunger and boosts fat burning, is profoundly reduced in calorie-restricted diets.

4. The Total amount of calories you eat in a day DO matter for body composition, but whether that weight results in fat or muscle gain/loss depends on macronutrient ratios.

5. If you aren’t overeating, simply altering macronutrient ratios to manage insulin and the hormone response of food can lead to fat loss and significantly improve body composition.

Simply put a Calorie is not just a Calorie and therefore if you want long time success then you need to do more than follow Weight Watchers ‘Not Rocket Science’ principles.

References

Bray, G., Smith, S., et al. Effect of Dietary Protein Content on Weight Gain, Energy Expenditure, and Body Composition During Overeating. Journal of the American Medical Association. 2012. 307(1), 47-60.

Barr, S., Wright, J. Postprandial Energy Expenditure in Whole-Food and Processed-Food Meals: Implications for Daily Energy Expenditure. Food and Nutrition Research. July 2010. 2(54), 144-150.

Sumithran, P., Prendergast, L., et al. Long-Term Persistence of Hormonal Adaptations to Weight Loss. The New England Journal of Medicine. October 2011. 356(17), 1597-1604.