Sunday, August 26, 2012

How to Increase Your Metabolism

Increase Your Metabolism

If you're trying to lose weight, increasing your metabolic rate can enable you to lose more weight without cutting more calories. The commercialism surrounding "metabolism-enhancing products" has made it difficult to separate fact from fiction (or advertising), but you can find a few research-based suggestions here.

Understand what metabolism is. In the simplest terms, metabolic rate is the rate at which your body burns calories. Very few people have a fast metabolism. Surprisingly, overweight individuals have relatively fast metabolism because they weigh more, but if their weight is staying costant then their metabolism is not fast enough to offset their caloric intake.[1] The bottom line is that increasing your metabolism will enable you to level your diet and weight.

Determine what is influencing your metabolism. There are some factors that you can control and change, and some factors that you can't.
  • Age - Metabolic rate decreases 5% each decade, after the age of 40 [2], partly because of decreased muscle mass.
  • Gender - Men generally burn calories more quickly than women because they have more muscle tissue.[2]
  • Heredity - You can inherit your metabolic rate from previous generations.[2]
  • Thyroid disorder - Hypothyroidism (underactive thyroid gland) and hyperthyroidism (overactive thyroid gland) can slow down or speed up metabolism, but only 3% and .3% of the population have hypo- and hyperthyroidism respectively.
  • Weight - different tissues of your body contribute different amounts to resting metabolism. Muscle contributes more than fat per unit mass and, because it is denser than fat, muscle contributes much more per unit volume [2], but this may not be practically significant [3]. See "Weight training" below.
 Estimate your resting metabolic rate (RMR). RMR is often used interchangeably with basal metabolic rate (BMR). Although they are slightly different, estimating either is sufficient for the purpose of losing weight. What these equations will show you is, that if you weigh more, your RMR will be higher! To calculate your RMR, use the Mifflin-St Jeor equation (which is more reliable than the Harris-Benedict equation[4]). There are also calculators online that can do this for you:
  • RMR = 9.99w + 6.25s - 4.92a + 166g-161
    • w = weight in kilograms; if you know your weight in pounds, divide by 2.2 to get your weight in kilograms
    • s = height in centimeters; if you know your height in inches, multiply by 2.54 to get your height in centimeters
    • a = age in years
    • g = gender = 1 for males, 0 for females
Adjust your diet accordingly. Your RMR will tell you how many calories you need to maintain your body at rest. Your daily consumption to maintain your weight should be:[5]
  • RMR x 1.15
    • E.g. RMR = 2000, so the maintenance intake is 2000 x 1.15 = 2300
  • To lose weight safely, do not exceed your maintenance intake or have a caloric intake lower than your calculated RMR.
  • Count calories by recording what you eat and looking up how many calories each food item contains (either on the food packaging or in tables provided in books or online).
Eat small, frequent meals. People generally eat less overall when they eat small yet frequently. Consider eating fruits , oats or anything with a "high volume to calorie content" , eating healthy snacks will also increase metabolism.[2] A common myth is that fasting or restricting your consumption of food will send your body into starvation mode.
Eat small, frequent meals.While there is little or no evidence that supports this it is true that malnutrition is never the solution to losing weight and may pose a serious risk to your health and have adverse effects in the long run. [6]

Drink iced water. As with food, depriving your body of water can encourage it to "hoard" rather than "burn". When you drink ice cold water, your body burns calories warming it to body temperature. More than ninety percent of the chemical reactions in your body occur in water, so make sure you drink an appropriate amount of water.

Boost metabolism temporarily with aerobic exercise. Different activities burn different quantities of calories, but the important thing is to raise your heart rate and sustain the activity for approximately thirty minutes.
Boost metabolism temporarily with aerobic exercise.
Boost metabolism temporarily with aerobic exercise.

Boost metabolism in the long run with weight training. Muscle burns more calories than fat does (73 more calories per kilogram per day, to be exact)[2] so the more muscle you build, the higher your resting metabolic rate (RMR) will be. Every muscle cell that you gain is like a little factory that constantly burns calories for you, even while you sleep, and revs up when you exercise. This is the only way to increase RMR, which accounts for 60 to 70 percent of the calories you burn daily.[7] From a recent conservative estimate [8] one can extrapolate that in one year a person with 2.2 kg more muscle will burn calories corresponding to 1 kg of fat due to this muscle mass. Young healthy men typically have 35 to 50 kg of muscle mass [9] so the most muscular men in the range burn extra calories relative to the least muscular corresponding to 6.8 kg (15 pounds) of fat per year.