DHEA is a hormone that can help the body slow aging, burn body fat, enhance memory, prevent osteoporosis, and increase libido. Naturally produced and released by the adrenal glands, DHEA is ultimately converted into estrogen and androgen. With age, DHEA levels in the body naturally decline. DHEA has shown the power to enhance quality of life in older people, increasing their energy level and ability to handle stress. Adrenaline is a hormone secreted by the adrenal gland, which brings about the changes in the body known as the "fight or flight" reaction or "stress reaction". Some of the actions of this hormone on various bodily systems include increased metabolism, increased blood pressure, increased mental activity, increased blood flow to the muscles, and increased heart rate. These reactions prepare the individual to deal with perceived threats or stress by enhancing capabilities to fight or to flee. Cortisol is a steroid hormone made in the adrenal glands. It has several important functions in the body including roles in the regulation of blood pressure and cardiovascular function as well as regulation of the body's use of proteins, carbohydrates, and fats. Cortisol secretion increases in response to any stress in the body, whether physical (such as illness, trauma, surgery, or temperature extremes) or psychological. When cortisol is secreted, it causes a breakdown of muscle protein, leading to release of amino acids into the bloodstream. These amino acids are then used by the liver to synthesize glucose for energy. This process raises the blood sugar level so the brain will have more glucose for energy. At the same time the other tissues of the body decrease their use of glucose as fuel. Cortisol also leads to the release of so-called fatty acids, an energy source from fat cells, for use by the muscles. Taken together, these energy-directing processes prepare the individual to deal with stressors and ensure that the brain receives adequate energy sources. Insulin is a hormone that converts blood sugar, or glucose, into useable energy. The body maintains an appropriate level of insulin throughout the day. Normally, when the body senses a rise in glucose after meals, it triggers the pancreas to release insulin. This insulin acts as a kind of escort for glucose, allowing it to enter tissue cells. This process keeps the level of blood sugar in check. In a person without diabetes, the body releases the right amount of insulin as it's needed throughout the day. It also keeps insulin available for your body to use when you're asleep. For people with diabetes, the body no longer has an ability to produce or release the right amount of insulin. It's up to you to help your body do what it can no longer do naturally, with the help of insulin. Thyroid hormones, thyroxine (T4) and triiodothyronine (T3), are tyrosine-based hormones produced by the thyroid gland. They act on the body to increase the basal metabolic rate, affect protein synthesis and increase the body's sensitivity to catecholamines. Catecholamines can be any of a group of amines that have important physiological effects as neurotransmitters and hormones and include epinephrine, norepinephrine, and dopamine. The thyroid hormones are essential to proper development and differentiation of all cells of the human body, to various extents they regulate protein, fat and carbohydrate metabolism. Pregnenolone is a sterone that is manufactured in the body from cholesterol in the tiny energy cells called the mitochondria. Pregnenolone is the precursor of many steroids and as such is eventually converted into a multitude of steroids and neurosteroids.