Research has shown that Keeping insulin levels at a stable level can promote a longer, healthier life. High levels of insulin and insulin resistance (when the body doesn’t respond well to insulin) are linked to a higher risk of age-related diseases. These diseases include neurodegenerative conditions, hypertension, cardiovascular disease, and type 2 diabetes.
When insulin levels are high, it encourages the body to store more fat, make more proteins that don’t work well, and reduces the body’s ability to clean out damaged cells. This can lead to problems in the cells’ energy factories (mitochondria) and increase stress from harmful molecules (oxidative stress).
As people age, their bodies become less responsive to the protective effects against insulin-induced stress. This resistance increases insulin levels and reduces the activation of protective pathways. However, adopting a lifestyle that keeps insulin levels low and boosts the body’s stress response, such as through a healthy diet and regular exercise, can help counter these negative effects.
Studies show that insulin may have aging-promoting effects in humans. Insulin resistance tends to increase with age, but those who live to be 100 or more often have better glucose tolerance, lower fasting insulin levels, and higher insulin sensitivity compared to those over 75. Additionally, shorter men who live longer tend to have lower fasting insulin levels.
In summary, managing insulin levels through diet and exercise can help promote a longer and healthier life.
Decreased levels of insulin over time promotes longevity. In humans, hyperinsulinemia and concomitant insulin resistance are associated with an elevated risk of age-related diseases suggestive of a shortened healthspan. Age-related disorders include neurodegenerative diseases, hypertension, cardiovascular disease, and type 2 diabetes. High ambient insulin concentrations promote increased lipogenesis and fat storage, heightened protein synthesis and accumulation of non-functional polypeptides due to limited turnover capacity. Moreover, there is impaired autophagy activity, and less endothelial NO synthase activity. These changes are associated with mitochondrial dysfunction and oxidative stress. The cellular stress induced by anabolic activity of insulin initiates an adaptive response aiming at maintaining homeostasis, characterized by activation of the transcription factor Nrf2, of AMP activated kinase, and an unfolded protein response. This protective response is more potent in the long-lived human species than in short-lived models of aging research resulting in a stronger pro-aging impact of insulin in nematodes and fruit flies. In humans, resistance to insulin-induced cell stress decreases with age, because of an increase of insulin and insulin resistance levels but less Nrf2 activation. These detrimental changes might be contained by adopting a lifestyle that promotes low insulin/insulin resistance levels and enhances an adaptive response to cellular stress, as observed with dietary restriction or exercise.
“In humans, epidemiological studies suggest a pro-aging effect of insulin. Insulin resistance increases with aging, but centenarians usually preserve normal glucose tolerance, low levels of fasting insulin and higher insulin sensitivity, when compared with adults > 75 years of age (52–54). The higher longevity in shorter men is also associated with lower fasting insulin concentrations (55).
