I am sure if you go around asking individuals what they think the most important meal of the day is, more than likely they will say Breakfast. However, some neuroscientists are beginning to suggest skipping breakfast 2 times a week to give your brain an extra kick. This “meal-skipping” is a form of intermittent fasting that has been a long-standing practice in many athletes and in religious practices. Though, this concept of intermittent fasting is not new, it is only starting to be examined as a treatment for obesity and reduction of hypothalamic inflammation.
One reason obesity is believed to occur is by signaling dysfunction of insulin and leptin receptors. If someone continues to eat saturated fatty acids, this may trigger a receptor called TLR4, which is activates inflammatory signaling cascades. This begins a cascade to trigger IKK which inhibits IKba. This inhibition allows for NFKbeta to enter the nucleus and release SOCS. This molecule inhibits the leptin receptor. This leptin receptor is responsible for releasing STAT into the nucleus causing activation of POMC and inhibition of AGrP to cause the body to tell the brain the body is full and stop-eating. Also, if the insulin receptor is inhibited in any way, such as the TNFalpha phosphorylating the IRS-1 molecule. This inhibition of IRS-1 causes a cascade to inhibit Akt from kicking FOXO out of the nucleus. If FOXO is not kicked out of the nucleus, FOXO will inhibit STAT and will not signal the brain that it is full.
There are multiple ways for someone to intermittent fast. One way is to do a caloric restriction of total calorie intake by 20-40%. If you sustain caloric restriction for several months to years, researchers have begun to notice several benefits, such as:
- Increased longevity
- Decrease in resting heart rate and blood pressure
- Increase in heart rate variability
- Increased insulin sensitivity
- Lower incidence of diabetes
- Decrease of body fat percentage
Another way to intermittent fast is do alternate day fasting (ADF) which consists of a 24-hour period of fasting and a 24-hour period of feasting. This has begun to show benefits such as:
- Extended lifespan in rat models
- Delay or prevention of cardiovascular disease, kidney disease, cancer, and diabetes
- Increased BDNF
- Decreased heart rate and blood pressure
- Improved insulin sensitivity in men ONLY
- Impaired glucose tolerance in women ONLY
Once the body has burned through the glucose in the liver, the body will begin to burn through ketone bodies and other fatty acids in the body. These ketone bodies are believed to be associated with health and aging. If this idea of intermittent fasting is sustained through multiple months or years, it is believed to improve memory, executive function, and cognition. This has also been seen to suppress inflammation and reduce risk of onset of neurodegenerative diseases, such as Alzheimer’s.
To put this in perspective, let us look at common religious practices. In Ramadan, a month-long Islamic practice, individuals will fast during daylight hours and join in a feast with family once the sun has set. In Jainism, monks and nuns will attempt to reduce their negative karma by not preparing food themselves and by only eating once a day. Some individuals may think of both these practices being extreme, however some researchers may think this as a positive practice. Though both these traditions cannot be generalizable to the general public due to the short duration of Ramadan and the vast differences in lifestyle in Jain monks and nuns.
Even if this benefits seem to be amazing, word of caution that you should be relatively well on emotional health and have a healthy diet. So, if you want to start, take it slow and safely.
