Calories
Crave them count them, or cut them, we all need a certain number of calories to provide us with energy through the day. The amount of calories in food is the measure of how much potential energy a food contains. This varies depending on the type of food. For example, a gram of carbohydrate or protein contains 4 calories, and a gram of fat contains 9. Exactly how many calories we need every day depends on our height, weight, age, gender, and activity levels. In general, adult men need about 2,500 calories a day and adult women about 2,000 (children need fewer).
Too Many Calories
We burn calories by breaking them down through metabolism (chemical processes in the body). If we consume more calories than we can burn, the excess is stored as fat. For example, if we consume 3,500 calories in excess of our needs, this is stored on the body as 1 lb (0.5 kg) of fat. Being overweight is associated with serious health risks.
Going For the Burn
Physical activity burns calories, which is why it is important to balance diet with exercise. Light activity burns fewer calories than strenuous activity. An activity such as running burns more than 300 calories in 30 minutes.
The Beating Heart
Even when we are at rest, the heart is busy pumping blood, the lungs are inflating and deflating, and our other organs are working. The amount of energy needed just to keep us idling along is called the basal metabolic rate. About 60-70 percent of the calories burned in a day are used up on basic bodily processes.
Comparing Calorific Values
Different foods contain different amounts of calories. Each food item on the left contains about 100 calories. A small piece of fatty food such as cheese shares the same calorie count as a whole bowl of a non-fatty food such as cherry tomatoes. Whether fat, protein, or carbohydrate, a calorie is a calorie. This means that any type of food can be fattening if we eat it in sufficient amounts.
Pepsin Enzyme
Calories are burned in complex metabolic processes in which enzymes (protein substances) play a critical role. Enzymes break down carbohydrates into sugars, fats into fatty acids and glycerol, and proteins into amino acids. Pepsin, an enzyme secreted by the stomach, breaks down protein into peptides (chains of amino acids).
To Your Health?
Although alcoholic drinks do provide some vitamins and minerals, calories from wine, beer, and liquor do not offer the best nutritional value. In addition, excess alcohol consumption can cause weight gain over time-there are 7 calories in one gram of alcohol.
Cold Comfort
It takes energy to digest food, but some people mistakenly believe that the process of warming up cold foods, such as ice cream, inside your body requires more energy than is present in the food itself. Sadly, ice cream is far from being a calorie-free treat.
Why organic?
Organic food is produced using farming methods that do not harm the environment. This means that no long-lasting chemical pesticides or fertilizers are sprayed on growing crops, and livestock is raised without hormones or antibiotics. Land must also be farmed organically for several years before crops may be labeled organic. In the United States, the Department of Agriculture allows qualifying producers to use the “USDA Organic” label on their packaging. Organic foods account for about 1-2 percent of worldwide food sales. In recent years, concerns about food safety, environmental pollution, and GM crops have increased consumer interest in organic foods. Today, organic food products represent the fastest-growing segment of food sales. Yet debate continues as to whether organic food really is better for our health.
