Answer to Question 1
A healthy weight-loss and weight-maintenance program consists of three components:
Setting reasonable goals: When it comes to weight loss, slow and steady is the way to go, and weekly weight loss should not exceed 1-2 pounds. Rather than making dramatic dietary changes, small changes such as reducing portion sizes and cutting back on energy-dense snack foods can make a big difference in overall energy intake.
Choosing nutritious foods in moderation: Weight-loss plans that drastically reduce caloric intake and offer limited food choices often leave people feeling hungry and dissatisfied. A key recommendation in the 2015 Dietary Guidelines for Americans is for people to develop eating patterns that emphasize a variety of nutrient-dense foods within all food groups, but at an appropriate level of calories.
Increasing energy expenditure through daily physical activity: In addition to choosing nutritious foods in moderation, you can also help tip the energy balance equation toward negative energy balance by engaging in physical activity. Walking 1 mile each day, which takes people about 15-20 minutes, uses about 100 kilocalories.
Answer to Question 2
TEF is the energy required to digest, absorb, and metabolize nutrients following a meal. In other words, it is the cost associated with your body's utilization of the foods you eat. The amount of energy associated with TEF depends on the amount of food consumed and the types of nutrients present in that food. In general, more energy is required to process large amounts of food, and high-protein foods have higher TEFs than do fatty foods. Considering that meals generally contain a mixture of nutrients, TEF is estimated to be about 5-10 percent of total energy intake. For example, after consuming a 500-kilocalorie meal, a person typically expends 25-50 kilocalories (TEF) just to digest and utilize the nutrients it contains.
