Science Based Six Pack At-Home Fasting Program

Intermittent fasting enhances hormone function to facilitate weight loss. As the research shows, lower insulin levels and increased amounts of norepinephrine (noradrenaline) all increase the breakdown of body fat and facilitate its use for energy. For this reason, short-term fasting actually increases your metabolic rate by 3.6-14%, helping you burn even more calories (1, 2). In other words, the practice of intermittent fasting works on both sides of the calorie equation. It boosts your metabolic rate (increases calories out) and reduces the amount of food you eat (reduces calories in). According to a 2014 review of the scientific literature, intermittent fasting can cause weight loss of 3-8% over 3-24 weeks (3). This is a huge amount! The study also demonstrates that the people also lost 4-7% of their waist circumference, which indicates that they lost lots of belly fat, the harmful fat in the abdominal cavity that causes disease.

What is good for the body is often good for the brain as well. Intermittent fasting improves various metabolic features known to be important for brain health (4). IF has demonstrated its ability to affect energy and oxygen radical metabolism, and cellular stress response systems, in ways that protect neurons against genetic and environmental factors to which they would otherwise succumb during aging (5). Fasting increases the presence of drebrin, a protein that regulates neuronal development (5). The loss of drebrin results in cognitive impairment that causes neurological disorders (5). Intermittent fasting is associated with the growth of the hippocampus, which is responsible for emotion and memory (5). Several studies in rats have shown that intermittent fasting may increase the growth of new nerve cells, which should have benefits for brain function (6, 7). It also increases levels of a brain hormone called brain-derived neurotrophic factor (BDNF) (8, 9, 10), a deficiency of which has been implicated in depression and various other brain problems (11).

Norepinephrine, a stress hormone that improves alertness, energy levels, and attention, is involved in the "fight or flight" response (12). It has a variety of other effects on your body, one of which is telling your body's fat cells to release fatty acids (burn fat). Increases in norepinephrine generally lead to larger amounts of fat being available for your body to burn. Fasting leads to a rise in the amount of norepinephrine in your bloodstream (13, 14). It's also been claimed that intermittent fasting could help an individual maintain muscle mass better than calorie restriction due to its effect on fat-burning hormones (18, 19). In particular, the increase in one specific hormone (see study) observed during fasting could help preserve muscle mass, even if you are losing weight (20). A 2011 review found that intermittent fasting was more effective at retaining muscle during weight loss than a traditional, low-calorie diet (21).