According to a recent editorial by three researchers specializing in human biology, while physical activity can stave off the effects of several common and debilitating diseases, when it comes to weight loss, the devil is in the diet.

"A recent report from the UK's Academy of Medical Royal Colleges described 'the miracle cure' of performing 30 min of moderate exercise, five times a week, as more powerful than many drugs administered for chronic disease prevention and management," they write. "Regular physical activity reduces the risk of developing cardiovascular disease, type 2 diabetes, dementia and some cancers by at least 30 percent. However, physical activity does not promote weight loss."

Source 

http://bjsm.bmj.com/content/early/2015/

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A few months ago, a family member of mine made the commitment to start losing weight and improve his health. From what I gathered in our conversations, he wasn't satisfied with his appearance, and the extra weight made him feel unproductive and sluggish. As a result, he decided to limit his caloric intake by taking on the ketogenic diet, which is a diet associated with low carbohydrate intake. By lowering the total number of calories, he felt he could begin to lose the weight, and start to look thinner and healthier.

After a few weeks, I noticed a significant improvement in his appearance – he stayed true to his word by choosing foods that were nutritionally adequate, and had avoided excessive consumption. I was impressed, I felt he'd finall ...