According to the US FDA Healthy weight is a body weight that is appropriate for your height and benefits your health. The healthy weight theory is also commonly known as the Set-Point Theory.
Living in a body considerably heavier than its healthy weight promotes increased risk of asthma, heart disease, high blood pressure/hypertension, osteoporosis and arthritis, Type 2 diabetes, gallstones, stroke, and certain types of cancer (esp. colon, breast, and female reproductive system). Obesity has also been associated with increased risk of problems with anxiety and depression.
As much as we may desire to be more slender than our healthy weight, it is not in alignment with our ideal health and overall wellness. The foundation of a successful weight loss program is a shift in consciousness towards a proper weight management program geared, one focused on reaching and sustaining an individual bodys healthy weight.
BMI - The FDA recommends a measuring tool called the BMI or Body Mass Index for helping determine whether you are at a healthy weight for you or if are underweight or overweight. The BMI is based on a persons height and weight. A BMI of 19-24 is considered a healthy weight, under 19 is considered underweight, 24-29 is considered overweight, and 30+ is considered obese. The US Dietary Guidelines for Americans references a BMI chart for adults over the age of 20 to use in identifying where they fall in this spectrum.
One important component of a healthy weight that the Body Mass Index doesnt account for, however, is the bodys percentage of body fat to muscle mass. An easy way to estimate your body fat percentage is to measure your waist with a tape measure. This measurement approximates your bodys amount of visceral fat. Generally speaking, and according to the National Heart Lung, and Blood Institute of the National Institutes of Health, a male with a waist circumference more than 40 in. (101.6 cm) and a female with a waist circumference more than 35 in. (88.9 cm) is at greater risk of disease than those with waist circumferences less than that.
Design your weight objectives, then, not around those pants you want to fit into, but around your ideal BMI-range and body fat percentage. The formula from there is simple:
Consume more energy (calories in food) than you burn (through activity and exercise) to gain weight;
Burn more energy than you consume to lose weight;
Strike a balance between how much energy you consume and how much you burn to maintain your existing weight.
Many factors influence your healthy weight age, genetics, metabolism, diet, and lifestyle (thats your habits and behaviors) but only certain of those factors can you do anything about. Theres no sense bemoaning age or genetic history, but you can effect enormous changes in your metabolism (and thus your weight) by making changes in your diet and lifestyle.
When youre at your healthy weight, you feel good and have all the energy you need (and more) for your work and leisure activities.