Smoking and drinking have both been proven to increase tissue damage through cellular oxidative stress, and eliminating both is one of the most common pieces of health and fitness advice. Both alcohol and nicotine have multiple programs dedicated to managing addiction, however for non-addictive substances it can be difficult to remove them from lifestyle correctly.
One of the best examples of this is food. We put food into our body every day but problems can come about if we consume too much or too little. Nutritional changes can create risk if calorie intake drops below what is needed to repair and maintain the body for extended periods of time. Calories are used to repair everyday wear on the body and to help replace cells, without this tissues are unable to repair. It’s one of the main reason that crash dieting can create more problems than solutions.
Controlled intermittent fasting has been shown to have numerous health benefits in those who are overweight( Anton, et al., 2018). When regarding an uncontrolled or crash diet especially for the average to underweight population, and for extended period of time, guidelines state that a reduction of just 500 calories below a baseline of 2000 is enough to increase risk of injury due to lack of repair. To combat this make sure to avoid extended periods of caloric depletion, perhaps practicing reducing caloric intake on alternate days. The exact pattern of calorie change will be dependent on your activity schedule.