A particular diet may be chosen to seek weight loss or weight gain. Changing a subject's dietary intake, or "going on a diet", can change the energy balance and increase or decrease the amount of fat stored by the body. Some foods are specifically recommended, or even altered, for conformity to the requirements of a particular diet. These diets are often recommended in conjunction with exercise. Specific weight loss programs can be harmful to health, while others may be beneficial and can thus be coined as healthy diets. The terms "healthy diet" and "diet for weight management" are often related, as the two promote healthy weight management. Having a healthy diet is a way to prevent health problems, and will provide the body with the right balance of vitamins, minerals, and other nutrients.
People talk about “weight” loss because scale weight is a proxy measure for fat loss. Fat is the major source of excess body mass for most people who want to “lose weight.” Measuring fat (by DEXA scans or other body composition tools) is expensive and difficult; measuring weight is cheap and easy. So people just measure weight and assume that if they lose weight, it’s because they’re losing fat.
If you don’t have an established exercise routine, simply walking is the best first step toward weight loss. “Walking is a pretty good entry point for people,” says Gagliardi. This is particularly true if you have been out of the gym for a while and want to ease back into a workout routine. One small study published in The Journal of Exercise Nutrition & Biochemistry found that obese women who did a walking program for 50 to 70 minutes three days per week for 12 weeks significantly slashed their visceral fat compared to a sedentary control group.