Want to Lose Weight? Quantity of Calories Matters More Than Type

A new study by Hall and colleagues (2015) demonstrated that a low fat diet is slightly better for reducing body fat than a low carb diet ( both were effective though).

Abstract: Summary Dietary carbohydrate restriction has been purported to cause endocrine adaptations that promote body fat loss more than dietary fat restriction. We selectively restricted dietary carbohydrate versus fat for 6 days following a 5-day baseline diet in 19 adults with obesity confined to a metabolic ward where they exercised daily. Subjects received both isocaloric diets in random order during each of two inpatient stays. Body fat loss was calculated as the difference between daily fat intake and net fat oxidation measured while residing in a metabolic chamber. Whereas carbohydrate restriction led to sustained increases in fat oxidation and loss of 53 ± 6 g/day of body fat, fat oxidation was unchanged by fat restriction, leading to 89 ± 6 g/day of fat loss, and was significantly greater than carbohydrate restriction (p = 0.002). Mathematical model simulations agreed with these data, but predicted that the body acts to minimize body fat differences with prolonged isocaloric diets varying in carbohydrate and fat.

What does this mean? It means that if you need to lose weight, you’ll probably do better with cutting back on your calories rather than changing what you’re eating. It’s easier to eat less of the same rather than less of something different. Of course, if your diet lacks your basic nutritional needs, you’ll have to change (add vegetables and some fruits), but in general just eat less.

I burn about 2000 calories per day with just normal activities (based on my height, weight, gender, etc). This means if I wanted to lose weight I’d need to consume fewer than 2000 calories per day. It takes about 3500 calories to lose a pound. That’s not exact and isn’t exactly true because if you consume fewer calories, your body tries to maintain weight by burning fewer calories. However, at some point if you restrict your caloric intake under your daily “burning” of calories, you will lose weight. The other thing you can (and probably should) do is exercise.

Men burn about 120 kilocalories per mile while running (this is weight and speed dependent) but only burn about 85 per mile walking. Women burn about 100 per mile running (again, weight and speed dependent) and about 75 per mile walking (source: http://www.runnersworld.com/weight-loss/how-many-calories-are-you-really-burning). Factor in how much you burn throughout the day (sex and weight-dependent in addition to how active you are) and there’s your caloric target to be under.

Summary

  • Eat less (particularly fat)
  • Exercise more

Reference

Kevin D. Hall, Thomas Bemis, Robert Brychta, Kong Y. Chen, Amber Courville, Emma J. Crayner, Stephanie Goodwin, Juen Guo, Lilian Howard, Nicolas D. Knuth, Bernard V. Miller III, Carla M. Prado, Mario Siervo, Monica C. Skarulis, Mary Walter, Peter J. Walter, Laura Yannai, Calorie for Calorie, Dietary Fat Restriction Results in More Body Fat Loss than Carbohydrate Restriction in People with Obesity, Cell Metabolism, Available online 13 August 2015, ISSN 1550-4131, http://dx.doi.org/10.1016/j.cmet.2015.07.021. (http://www.sciencedirect.com/science/article/pii/S1550413115003502)

Be Sociable, Share!

Leave a Reply

Your email address will not be published. Required fields are marked *