Human growth hormone (HGH) is an important hormone produced by your pituitary gland.
Also known as growth hormone (GH), it plays a key role in growth, body composition, cell repair and metabolism (1, 2, 3, 4, 5, 6).
HGH also boosts muscle growth, strength and exercise performance, while helping you recover from injury and disease (4, 7, 8).
Lower HGH levels may negatively impact your quality of life, increase your risk of disease and make you gain fat (9).
Optimal levels are especially important during weight loss, injury recovery and athletic training (10, 11, 12, 13).
Interestingly, your diet and lifestyle choices can have a huge effect on your HGH levels (6, 14).
Here are 11 evidence-based ways to increase human growth hormone (HGH) levels naturally.
1. Lose Body Fat
The amount of body fat you carry is directly related to your HGH production (3).
Those with higher body fat levels or more belly fat will likely have impaired HGH production and an increased risk of disease.
One study observed that individuals with three times the amount of belly fat as the control group had less than half their amount of HGH (15).
As shown in the graph below, one study monitored the 24-hour release of HGH and found a large decline in those with more abdominal fat.
Interestingly, research suggests that excess body fat affects HGH levels more in men. However, lowering body fat is still key for both genders (15, 16).
One study found that obese individuals had lower levels of IGF-1 — a growth-related protein — as well as HGH. After losing a significant amount of weight, their levels returned to normal (17).
Belly fat is the most dangerous type of stored fat and linked to many diseases. Losing belly fat will help optimize your HGH levels and other aspects of your health.
Get rid of excess body fat — especially around your belly — to optimize your HGH levels and improve your health.
2. Fast Intermittently
Studies show that fasting leads to a major increase in HGH levels.
One study found that three days into a fast, HGH levels increased by over 300%. After one week of fasting, they had increased by a massive 1,250% (18).
Other studies have found similar effects, with double or triple HGH levels after just 2–3 days of fasting (19, 20, 21).
However, continuous fasting is not sustainable in the long term. Intermittent fasting is a more popular dietary approach that limits eating to brief time periods.
Multiple methods of intermittent fasting are available. One common approach is a daily eight-hour eating window with a 16-hour fast. Another involves eating only 500–600 calories two days per week (22, 23).
Intermittent fasting can help optimize HGH levels in two main ways. First, it can help you drop body fat, which directly affects HGH production (24, 25, 26, 27).
Second, it’ll keep your insulin levels low for most of the day, as insulin is released when you eat. Research suggests that insulin spikes can disrupt your natural growth hormone production (28, 29).
As shown in the graph below, one study found large differences in HGH levels on the fasting day compared to the eating day (30).