Weight-Loss Myths Refuted in New Review

No topic in the world of health and fitness excites as much comment or discussion as weight loss. Consequently, most of us have several firm beliefs in our head on 'what works' and what does not. However, as you will read below, many of these beliefs are only half-truths and often are downright false. A special article published in one of the most respected medical journals, was published a few days back which debunked many of the myths. These myths are listed below, and I have added 'my take' to each of them, for what its worth!

The findings were published online January 31 in a special article in the New England Journal of Medicine. Here is a link to the article, but you need to be a member to read the whole article:

http://www.nejm.org/doi/full/10.1056/NEJMsa1208051?query=featured_home


The below article on the subject has been pasted from theheart.org, and the full link for the article is below.

http://www.theheart.org/article/1501837.doutm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+Theheartorg+(theheart.org)

The authors discuss a total of 7 myths, along with refuting evidence. Here are some examples:

Small changes in food intake and/or exercise will produce large, long term weight changes — This idea was based on the old idea that 3500 kcal equals 1 pound of weight. But it does not take into account the fact that energy requirements change as body mass changes over time. So, as weight is lost, it takes increasingly more exercise and reduced intake to perpetuate the loss.

My take: In other words, as you begin losing weight you will need to curb your caloric intake further and / or increase your caloric output to continue losing weight at the same pace.


Realistic weight-loss goals will keep people motivated — This idea seems reasonable, but it is not supported by evidence. In fact, several studies have shown that people with very ambitious goals lose more weight (eg, TV's The Biggest Loser).

My take: Actually, I used to believe in realistic and gradual weight loss goals too, and still do, but with a caveat. I have realized that for those who are very heavy (say, at least 30 kg above ideal body weight), gradual weight loss does not work. One of the reasons, in my opinion, is that a 6-8 kg weight loss (which may take a few months, when done 'sensibly') usually, does not show on the person, and no one notices. I feel, that positive feedback and 'wow' comments from near and dear ones go a long way in keeping up motivation, and often gradual weight loss does not lead to that.


Slow, gradual weight loss is best for long-term success — Actually, a meta-analysis of randomized, controlled weight-loss trials found that rapid weight loss via very-low-calorie diets resulted in significantly more weight loss (16% vs 10% of body weight) at 6 months, and differences in weight loss persisted up to 18 months (Int J Behav Med. 2010;17:161-167).

My take: I am surprised to know that the weight loss persisted up to 18 months. Will need to read the entire article to be satisfied on this one.


A bout of sexual activity burns 100 to 300 kcal per person — With intense sexual activity, a 154-pound man burns approximately 3.5 kcal per minute. However, given that the average amount of time spent during one stimulation and orgasm session is about 6 minutes, this man might expend about 21 kcal total. But, he would burn about 7 kcal per minute just lying on the couch, so that amount has to be subtracted, which gives a grand total of 14 kcals of energy expended.

My take: So much for all the 'studs' who thought they were getting a great workout between the sheets.

The article also explores 6 "presumptions," or widely accepted beliefs that are neither proven nor disproven. Among them:


Eating breakfast prevents obesity — Actually, 2 studies showed no effect of eating vs skipping breakfast.


Adding fruits and vegetables to the diet results in weight loss — Adding more calories of any type without making any other changes is likely to cause weight gain. Eating fruits and vegetables is healthful, however.


Weight cycling, aka "yoyo dieting," increases mortality — The data are from observational studies and likely confounded by health status.

Finally, the authors offer 9 facts about obesity and weight loss that are supported by data, among them:

Moderate environmental changes can promote as much weight loss as even the best weight-loss drugs.

Diets do produce weight loss, but attempting to diet and telling someone to diet are not necessarily the same thing.

Physical activity does help in promoting weight loss and has health benefits even in the absence of weight loss.

For overweight children, involving the family and home environment in weight-loss efforts is ideal.

Providing actual meals or meal replacements works better for weight loss than does general advice about food choices.

Both weight-loss drugs and bariatric surgery can help achieve long-term weight loss in some individuals.