Leptin Resistance 3

*Leptin part 3*

*What’s the problem with high leptin levels?*

In addition to controlling our satiety and influencing hormones, leptin is also an inflammatory molecule. High levels of leptin can create chronic inflammation and contribute to conditions such as autoimmunity and histamine intolerance (source 1, source 2).

High leptin and leptin resistance can also predispose people to other inflammatory diseases such as high cholesterol, heart disease, hypertension and diabetes (source). Neurosurgeon Dr. Jack Kruse believes that high leptin is the underlying issue that causes most modern chronic diseases, and that re-balancing leptin is the key to health (source).

*Causes of Leptin Resistance*

There are several factors that can contribute to leptin resistance. Here are some of the most common ones:

*Circadian rhythm dysregulation*

As we’ve covered before, bright blue/green light early in the morning stimulates the release of a hormone that helps us with focus and alertness, but that same light can make it hard to fall asleep if we’re exposed to it at night. (That’s why I wear these blue blocking glasses after sundown.)

In the same way, our bodies respond to feast/fast cycles that are tied into our circadian rhythm. (source) The ebb and flow of two hormones, leptin and insulin, alternates our bodies between fat burning and fat storing modes.

In the daytime we are in energy burning mode, which makes sense because it’s when we’re most active. At nighttime, our bodies go into “cleanup mode” – also known as autophagy. Historically, our schedules naturally aligned with these rhythms – eat for fuel in the day and rest in the evenings. These days, though, we often stay up late and snack late into the evening, which can throw off the ebb/flow rhythm of this rhythm.

“Eating within three hours of bedtime – late-night snacking – sends blood and heat to your core, which is a signal to the body to stay awake,” writes Dr. Michael Breus, who is a Diplomate of the American Board of Sleep Medicine, Fellow of The American Academy of Sleep Medicine, and the author of The Power of When.

In addition to signaling our bodies to stay awake, eating late at night alters the way our bodies respond to leptin. One of the best ways to increase leptin sensitivity is to restore the natural feast/fast cycle by fasting 10-12 hours between the last meal of one day and the first meal of the next morning.

(Note from Heather: I fast from 8pm to 8am most days. It was difficult at first because I was a late-night snacker, but after a while I found that I no longer had cravings before bed. Intermittent fasting helped me improve my leptin sensitivity, which had become an issue after my third baby was born.)

*Lack of deep, restorative sleep*

Although related to the section on circadian rhythm above, there are times when poor sleep is not associated with circadian rhythm dysregulation. If you are sleeping enough but don’t wake feeling rested, it might be worth asking your doctor for a referral to a sleep medicine specialist to screen for issues that may prevent you from getting restful sleep. For example, sleep apnea and airway problems that restrict breathing at night (hypopnea) may cause leptin resistance, metabolic syndrome, depression, and many other health problems (source, source 2).

You might have noticed before that you get much hungrier after a night of poor sleep. That’s because lack of sleep both reduces the amount of leptin in your body and makes you leptin resistant. (source) For more information on getting deeper, more restful sleep, check out 18 Science-Backed Sleep Tips.

*Inflammation*

Inflammation of the hypothalamus can cause leptin resistance, which is why some people find it difficult to lose weight when consuming inflammatory foods (foods they are sensitive to) or struggling with a chronic infection. Toxic molds and other sources of inflammation in the environment can also cause leptin resistance. (source)

Inflammation and weight gain can be a vicious cycle. High body fat is inflammatory, which causes leptin resistance, which can cause more weight gain. While the fat needs to be burned off, sometimes the key to doing that is to reduce inflammation.

*Aging*

It does get harder to lose weight as we get older. One of the key genes that leptin turn on in the hypothalamus is the longevity gene called Sirtuin1 (source). If this anti-aging gene does not work well, it can cause leptin resistance. Fortunately, there are many ways that we can improve the function of the Sirtuin gene and slow down aging, which maintains leptin sensitivity.