Greetings Gang, Dr T here
So what is intermittent fasting, and why is it so awesome?
Intermittent fasting (IF) is not a diet, it’s a lifestyle in which you limit food intake to a certain time window during the day. For example, I eat all my meals within a 12 hour window between 8am and 8pm, and I fast through the evening and while I’m sleeping.
There are a lot of patterns of intermittent fasting, such as:
- Eating all meals within a 12 hour window (say, from 8am – 8pm), then fasting for 12 hours
- Eating all meals within a 10 hour window (usually 9am – 7pm), then fasting for 14 hours
- Eating all meals within an 8 hour window (usually 10am-6pm), then fasting for 16 hours (You’ll often see this referred to as 16:8 intermittent fasting)
- Every other day fasting (eating nothing one day, then eating normally the next)
- Extended fasting
Although there may be certain situations when longer fasts might be appropriate, more is not usually better when it comes to intermittent fasting. Extended fasts can disrupt hormone balance – especially in women – which can lead to poor sleep, fatigue, fertility issues, depression, and other problems.
On the flip side, a daily fasting cycle works to balance the ebb and flow of leptin (the fat burning hormone), insulin (the fat storage hormone), and other hormones that we make throughout the day. According to Dr. Lori Rose, who is my co-author for this post, that’s because our digestive tract contains a “peripheral body clock” that syncs up with our 24-hour circadian rhythm, and periods of daily feasting/fasting help “set” the clock in the same way that light and dark does.
1: Weight Loss/Healthy Metabolism
Remember how I said it’s not so much about what you eat, but when? Here’s a study from Salk University that explains what I mean:
We put two groups of mice on different eating regiments for 100 days. Both groups ate a high-fat, high calorie diet. The first group was allowed to eat whenever they wanted, grazing throughout the day and night. The other mice had access to food only for eight hours at night, since mice are nocturnal. The results were astonishing. Despite consuming the same amount of calories everyday, the mice that ate on a restricted eight hours were nearly 40 percent leaner and showed no signs of inflammation or liver disease and had healthy cholesterol and blood sugar levels. The group of mice that nibbled day and night became obese, developed high cholesterol, high blood sugar, fatty liver disease and metabolic problems.”
Even more fascinating is the fact that when the time-restricted feeding mice were allowed to eat freely on the weekends, they still had the same lean mass ratio as mice who were restricted seven days a week.
2: Activates “Cleanup Mode”
Intermittent fasting triggers autophagy, which is literally translated as “cellular eating.” When autophagy occurs, a bunch of little guys called lysosomes go around gobbling up damaged cells, damaged mitochondria, and cancerous cells. These lysosomes and mitochondria are good guys, giving us energy for vitality and cellular regeneration for a vibrant life. Without them, our body fills up with cellular trash and we just can’t function as optimally as possible. Furthermore, negative results like expedited aging and disease occurs because we just aren’t taking out the proverbial trash as efficiently as we should.
Unfortunately, although autophagy should occur naturally, factors like the Standard American Diet (SAD), non-stop grazing/snacking, and a stressful go-go-go lifestyle can suppress it. By intentionally triggering autophagy through intermittent fasting, we’re supporting:
- energy production
- free radical elimination
- and damaged cell elimination
3: Improves Learning & Memory
Intermittent fasting increases neuroplasticity (brain flexibility) and the production of new neurons, which “enhance learning and memory.” This study also mentions that it dials up antioxidant defenses, autophagy and mitophagy (the cleanup of our cells and mitochondria), and DNA repair (which slows down aging).
4: Improves Immune Function
Mice that had been intermittent fasting had a stronger immune response to salmonella infection than those who hadn’t .
5: Lowers Inflammation
One of the main causes of inflammation is an excess amount of free radicals within the body, which causes cellular damage. Throughout our daily processes of just living, mitochondria – which are the “power plant [TEP]” in our cells that give us energy – get damaged. When mitochondria are damaged, they release free radicals which cause inflammation, age-related degeneration, as well as DNA damage.
Also, our energy is reduced due to the reduction in the number of functioning mitochondria. When we fast, we stimulate autophagy, which means that lysosomes gobble up these damaged mitochondria.
6: Activates Longevity Genes
“We found that intermittent fasting caused a slight increase to SIRT3, a well-known gene that promotes longevity and is involved in protective cell responses,” said Michael Guo, who co-authored this study. Another study also found that it increases levels of SIRT1, another longevity gene.
Most Americans don’t think they can miss a meal. But look at all the benefits from taking a break from eating