Wednesday, September 8, 2010
Weight-loss Myths, Part 3
We do this because, without you knowing it, the media has brainwashed us into believing the world is flat, and that and the sun revolves around the earth, when it comes to exercise, nutrition, and weight-loss. Why do they do this? Well, according to ResearchWikis.com:
"The sports drinks market is approximately US $300 billion in terms of sales worldwide in 2005."
Need I say more?
Just like Galileo was persecuted because he said the earth revolves around the sun, we too get strange looks and sometimes heated tempers when we say things like:
"Drink chocolate milk instead of protein drinks; and eat all the carbs you want, even after 6 o'clock."
So, for the next few days we are going to share some weight-loss myths that the National Academy of Sports Medicine outlines in their "Solutions to Weight Management" course. So far, we've tackled the high-carb/low-protein diet, eating at night causes weight gain, and you have to exercise at a low intensity or you won't burn fat. Let's tackle three more today:
The More You Cut Calories, the More Weight You’ll Lose
Yes and no. This text has reviewed the physiology of weight loss, and we have seen that an energy deficit must be created for weight loss to occur. However, Health and Fitness Professionals should caution their clients against going too low. Most nutrition experts do not recommend an energy intake any lower than 1,200 calories, and even that may be too low for an active or very large person.
Very-low-calorie diets (VLCD) should be followed only under the supervision of a medical professional.
A VLCD is a doctor-supervised diet that typically uses commercially prepared formulas to promote rapid weight loss in patients who are obese. These formulas, usually liquid shakes or bars, replace all food intake for several weeks or months. VLCD formulas need to contain appropriate levels of vitamins and micronutrients to ensure that patients meet their nutritional requirements. People on a VLCD consume about 800 calories per day or less (14).
VLCD formulas are not the same as the meal replacements sold at grocery stores or pharmacies, which are meant to substitute for one or two meals a day. Over-the-counter meal replacements such as bars, entrées, or shakes should account for only part of one’s daily calories. There is a good amount of evidence, including a recent meta-analysis, that supports the use of meal replacements for weight loss and maintenance (15).
When used under proper medical supervision, VLCDs may produce significant short-term weight loss in patients who are moderately to extremely obese. VLCDs should be part of a comprehensive weight loss treatment program that includes behavioral therapy, nutrition counseling, and physical activity. Additionally, long-term maintenance of weight lost with VLCDs is poor and no better than other forms of obesity treatment. Incorporation of behavioral therapy and physical activity in VLCD treatment programs seems to improve weight-loss maintenance (14).
Chapter 3, “Physiology of Weight Control” provided guidelines for estimating daily calorie needs, and those should be used when counseling clients on the dangers of restricting calories below recommended levels. Some of the risks of following an overly restrictive diet include:
• Increased risk of malnutrition.
• Poor energy and inability to complete the essential fitness program.
• A behavioral “pendulum” swing—an inability to reintroduce “forbidden foods” in a moderate manner.
• Reports from patients on a VLCD for 4 to 16 weeks of minor side effects such as fatigue, constipation, nausea, or diarrhea. The most common serious side effect is gallstone formation. People who are obese, especially women, are at a higher risk of getting gallstones, and they are even more common during rapid weight loss (14).
Health and Fitness Professionals should discourage overly restrictive programs advocating less than 1,000 to 1,200 calories per day, and support safe, maintainable weight loss by means of more healthful eating, smaller portions and increased activity.
Certain Foods, Like Grapefruit, Celery, or Cabbage Soup Can Burn Fat and Make You Lose Weight
These programs, often called “negative-calorie diets,” suggest that somehow certain foods create a negative energy balance. Recall from Chapter 3, “Physiology of Weight Control”, that, while there is a metabolic cost of digesting, absorbing, and transporting nutrients (called the thermal effect of feeding or TEF), experts do not consider it significant to weight loss. “Negative-calorie” diets are often disguised very-low-calorie diets that produce weight loss because of their severe energy restriction, not nutrient biochemistry. Additionally, most of these diets are limited to a small number of foods and do not provide adequate macro or micronutrients.
Low Fat or Fat Free Means “No Calories”
While this misunderstanding was more dominant during the low-fat 1980s and early 1990s, the premise has again taken hold with the “low-carb/no-carb” craze. The two share the same fallacy that if a product is “fat-free” or “low-carb” it is somehow calorie-reduced, or even calorie-free. The inverse is often true, as fat-free and low-carb products often contain large amounts of sugar, protein, or fat. Recall that any nutrient eaten in excess of the body’s needs (thus resulting in a calorie surplus) will be converted and stored as fat. Clients should be encouraged to follow healthy eating guidelines rather than to declare diabolic a single nutrient category in hopes of weight loss. However, if these foods help reduce total calorie intake, weight loss may occur provided that the total daily intake is less than calories expended.
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