We talk a lot about the effects of insulin on blood sugar, but we don’t often discuss the effects that insulin has on other health markers such as blood pressure. In this week’s blog, I am going to discuss just a couple of the mechanisms of how too much insulin can lead to having high blood pressure and why I believe that a diet that controls insulin will have positive effects for those attempting to control their blood pressure.
Aldosterone is a hormone that is released from the adrenal glands. Aldosterone’s job is to help regulate the balance of salt and water in our bodies. It does this by telling the kidneys to hold on to sodium and keep it in the blood rather than let it be eliminated out in the urine. Our bodies need to maintain a tight sodium to water balance in our blood for everything to work properly and so where sodium goes, water follows to keep things at a proper dilution. If there is too much aldosterone released, the kidneys will retain too much sodium and thereby too much water. This keeps the sodium balanced in the blood, but it adds extra volume and thereby pressure inside our blood vessels. Interestingly enough, insulin is known to increase aldosterone levels. If a person has too much insulin chronically, then their aldosterone is being stimulated too much which leads to more sodium and more water in the blood and can result in hypertension (high blood pressure).
Another way that too much insulin can contribute to high blood pressure is by its growth stimulating properties. Insulin is an anabolic hormone (meaning growth causing). Insulin signals cells to grow, including endothelial cells. Endothelial cells are the cells that line the innermost layer of our blood vessels. When normal levels of insulin are pumping though our blood, this stimulation is normal and healthy; however, when too much insulin is being pumped through our blood, this intensified stimulation to grow causes the endothelial cells to grow too much, thickening the innermost layer of our blood vessels causing the open area where blood can flow through to narrow and so increases blood pressure. Imagine trying to get a mouthful of water through a wide straw versus a tiny narrow straw and you will get the point.
While these are just a couple of the ways that insulin can potentially affect blood pressure, I think that the take home message is that the importance of eating a diet that contributes to high levels of insulin is not good for more than just blood sugar. The best way to lower insulin levels in the blood is through the use of time restricted eating/intermittent fasting and through a low-carbohydrate/low-glycemic diet. Are you interested in learning how to implement a low carbohydrate diet or intermittent fasting into your lifestyle? I would love to help you!
Forever Yours in Health,
Emalee