A lot of factors beyond your control help determine your basal metabolic rate, which is the number of calories your body needs to perform basic functions like breathing. Your age, gender and genes, for example, play a role in setting your BMR. Certain substances in foods and drinks may have a slight boosting effect on your metabolism, but they won't burn away calories on their own. If you've started gaining pounds suddenly or you can't seem to lose weight, speak with your doctor to rule out an underlying medical reason.
Weight Loss Basics
To lose weight, you need to create a calorie deficit through a combination of food choices and exercise. In general, you need to shave 3,500 calories from your regimen to lose 1 pound of body weight. The best way to accomplish this is slowly, through a combination of diet and exercise. To lose a pound in a week, you could trim 250 calories from your diet and burn an additional 250 calories through exercise.
Making a switch to healthier choices in food and drink, such as eating fruits and vegetables, lean protein, whole grains and drinking unsweetened beverages, will reduce your calorie intake. Whole foods tend to be less energy dense and more filling than sugary, fatty foods and drinks. If you're a cola drinker, for example, eliminating just one medium-sized fountain soda a day spares you about 275 calories, and would help you lose about 2 pounds in a month's time, without making any other dietary changes.
In addition, exercise is a proven way to give your metabolism a boost. Combine at least 150 minutes of aerobic activity a week, such as brisk walking, jogging, swimming, or an aerobics class, with two sessions of strength training with weights or resistance bands. A 155-pound person burns 260 calories in one 30-minute, low-impact aerobics class.
Caffeine in Coffee and Metabolism
When rethinking your drink choices, you'll be glad to know you don't need to eliminate coffee from your diet. Fifty milligrams of caffeine has a slightly thermogenic effect on your body, meaning it burns calories and raises BMR, according to a study published in the European Journal of Clinical Nutrition in 2009. A cup of brewed coffee has anywhere from 70 to 140 milligrams of coffee, depending on the type of beans and roasting used, and on the brewing method. Coffee from large national chains may contain more caffeine.
For the best results, drink your coffee black. If you use cream and sugar or order drinks loaded with syrup and whipped cream, you're adding empty calories that will defeat your weight-loss goals. While 16 ounces of dark roast coffee from a national chain has only 5 calories, the same sized, white chocolate mocha drink weighs in at a hefty 400 calories.
Daily consumption of up to 400 milligrams of caffeine is generally safe for healthy adults. More than that may produce side effects in some people such as a rapid heartbeat, anxiety, restlessness and insomnia.
Green Tea Catechins and Your Metabolic Rate
Research on green tea and metabolism has been conflicting. In the 2009 study mentioned above, green tea had no effect on thermogenesis at all. But other studies, including one published in Obesity in 2007, have shown that green tea's catechins – beneficial plant compounds – do decrease both body weight and body fat.
As with coffee, drink your green tea plain without added sweeteners, for the best results. If you prefer cold tea to hot, make your own from brewed tea instead of buying bottled tea; the catechins in bottled drinks degrade through the process of production, storage and transportation, according to a study published in the Journal of Agricultural and Food Chemistry in 2001.
Calcium From Dairy and Metabolism
Calcium intake contributes significantly to weight and fat loss, according to a review published in the American Journal of Clinical Nutrition in 2004. The author of the review concluded that three or more servings of dairy foods and beverages a day could speed up calorie-burning in adults. Dietary calcium works better than supplemental, he hypothesized, because the branched chain amino acids in dairy products' whey protein seem to support the effects. Drinking three glasses of milk a day may give your metabolism a boost.
Watch the fat content of your milk to control your calorie intake and reduce your unhealthy saturated fat intake. You don't need to drink full-fat milk to get the greatest amount of calcium. In fact, while a cup of whole milk has 276 milligrams of calcium and 149 calories, a similar serving of 1 percent milk has more calcium for fewer calories -- 305 milligrams of calcium for just 102 calories.