The Complete Guide To Fasting

by Jason Fung

Excessively low growth hormone levels in adults leads to more body fat, less muscle mass, and decreased bone density (osteopenia). Growth hormone, along with cortisol and adrenaline, is a counterregulatory hormone. These hormones signal the body to increase the availability of glucose—countering the effect of insulin and producing higher blood sugar levels. Levels of counterregulatory hormones peak just before waking, at approximately 4:00 a.m. or so, increasing blood sugar levels, which fall during the night. The increase prepares the body for the upcoming day by making more glucose available for energy. Growth hormone also increases the availability of fats for fuel by raising levels of key enzymes, such as lipoprotein lipase and hepatic lipase. Since burning fat reduces the need for glucose, this helps maintain stable blood sugar.