Insulin regulates blood sugar. The inability of cells to increase sugar uptake from the bloodstream (insulin resistance) predicts diabetes. Learn more about insulin’s function and the risk of abnormally high or low levels here.<\/p>\n
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Insulin is a hormone secreted by the pancreas. Insulin is responsible for lowering blood glucose<\/a> and storing this sugar into bodily tissues such as in muscles and the liver [R<\/a>, R<\/a>].<\/p>\n Insulin can be fattening<\/strong>. It increases fat synthesis and inhibits the breakdown of fat tissue. In addition, it promotes glucose uptake and its use to produce energy in the cells [R<\/a>].<\/p>\n Insulin also plays a role in suppressing glycogen conversion into glucose, which is released into the bloodstream, in the liver and muscles <\/strong>[R<\/a>].<\/p>\n Injectable insulin is approved to lower blood glucose in people with type 1 diabetes (who produce little or no insulin), as well as in those with type 2 diabetes (who fail to produce or use insulin normally) that cannot be controlled with oral medications. It is injected under the skin of the abdomen, legs, back of arms, or buttocks 30 minutes before a meal.<\/p>\n Multiple studies attest to its effectiveness [R<\/a>, R<\/a>, R<\/a>].<\/p>\n Insulin can enter the brain through the blood-brain barrier<\/a> and exert its effects via brain insulin receptors [R<\/a>].<\/p>\n In multiple clinical trials, intranasal insulin<\/a> improved cognitive function (especially story recall) in people with Alzheimer\u2019s and mild cognitive impairment. It also reduced a marker of Alzheimer\u2019s (and reduced a marker of this disease (tau-P181\/A\u03b242) [R<\/a>, R<\/a>, R<\/a>, R<\/a>, R<\/a>].<\/p>\n Insulin also improved memory and brain function in 2 clinical trials on 40 healthy people [R<\/a>, R<\/a>].<\/p>\n A hormone similar to insulin (IGF-1<\/a>) is associated with cognitive function in elderly people and seems to mediate the beneficial effects of exercise<\/a> on the brain [R<\/a>, R<\/a>].<\/p>\n In diabetic rats, insulin preserved nerve function preserved a marker of nerve health (myoinositol<\/a>) [R<\/a>].<\/p>\n In test tubes, both insulin and the similar proteins insulin-like growth factor 1<\/a> (IGF1) and 2 <\/a>(IGF2<\/a>) stimulated the growth of brain and nerve cells. In rats, IGF2 promoted the regeneration of damaged motor nerves [R<\/a>, R<\/a>, R<\/a>].<\/p>\n Taken together, the evidence suggests that insulin may improve brain function, especially in people with Alzheimer\u2019s or mild cognitive impairment. Because it\u2019s not approved by the FDA, you may only use it as an add-on if your doctor recommends it.<\/p>\n Insulin resistance is associated with an increased incidence of high blood pressure and coronary heart disease [R<\/a>, R<\/a>].<\/p>\n In multiple clinical trials on people with heart failure, the infusion of insulin, glucose, and potassium<\/a> improved heart pumping function [R<\/a>, R<\/a>, R<\/a>, R<\/a>, R<\/a>, R<\/a>, R<\/a>, R<\/a>].<\/p>\n However, 2 meta-analyses concluded that this combination doesn\u2019t reduce the death rate from heart attack or insufficient blood supply (acute coronary syndrome) [R<\/a>, R<\/a>].<\/p>\n Insulin forces the muscles in the artery walls to relax, thus increasing blood flow. Several human studies observed increased blood flow in the heart muscle after insulin administration [R<\/a>, R<\/a>, R<\/a>].<\/p>\n Insulin increased the production and secretion of a growth factor known to create new blood vessels (VEGF<\/a>) in a cell-based study [R<\/a>].<\/p>\n This hormone also inhibited platelet formation via an increase of a specific compound (cGMP), possibly reducing the risk of blood clots [R<\/a>].<\/p>\n Although a bit limited, the evidence suggests that insulin may help improve pumping function and blood flow. You may discuss with your doctor if it may help you prevent or improve heart condition. Importantly, never use insulin in place of what your doctor recommends or prescribes.<\/p>\n<\/a>Health Benefits<\/strong><\/span><\/h2>\n
<\/a>Effective<\/strong><\/span><\/h3>\n
<\/a>Lowering Blood Glucose<\/strong><\/span><\/h3>\n
<\/a>Possibly Effective<\/strong><\/span><\/h3>\n
<\/a>1) Brain and Nerve Function<\/strong><\/span><\/h3>\n
<\/a>2) Heart Function<\/strong><\/span><\/h3>\n