The number of calories you need to maintain or lose weight depends on a number of factors, including your age, sex, height, and level of physical activity, according to the FDA. To maintain a healthy body weight, the FDA recommends that you balance the number of calories you consume with the number of calories you burn through physical activity and your body’s metabolic processes. As a rule of thumb, the FDA recommends a standard 2,000 calorie diet for the average adult.
Aim to do ab work 3 or 4 times a week on non-consecutive days with at least 24 hours of rest in between sessions, says Gagliardi. During those sessions, you can start with simpler moves like crunches, bicycle crunches, and planks. Even though you may only be directly targeting your abs 3 or 4 times a week, you should still be activating your core (aka, tightening your ab muscles) in every workout you do, says Gagliardi.
This diet theory, consisting of 10% or less of daily calories from fat, is the flip-side to Atkins, Keto, and Paleo. Proponents of the ultra-low-fat approach adhere to a diet rich in plant foods, low in animal products, and high in carbohydrates (80% or more of daily caloric intake). An example of this type of theory is the TLC (Therapeutic Lifestyle Changes) Diet created by the National Heart, Lung, and Blood Association with the purpose of helping people combat heart disease, lower cholesterol levels, and prevent digestive problems.
Based on the concept of caloric density, which states that some foods have few calories in proportion to their size (say, a lettuce), while others have lots of calories packed in small portions (a regular chocolate chip cookie comes to mind), Volumetrics divides foods into 4 categories based on their calorie/volume ratio, and is perfect for people looking to binge on some foods while still shedding pounds. However, as with the calorie counting approach, Volumetrics does not take into account the quality of the calories, prioritizing quantity instead. The app Noom and Weight Watchers (both reviewed above) share similarities with this diet theory.