Time Restricted Eating By Mrs Vera West
The merits of fasting have been known for thousands of years by religious folk both West and East. Indeed, the feast/feast way of doing things was the main way of subsistence in the ancient past, and no doubt this is where humanity will return. But until that happy time, here is some info on the modern view of this, time restricted eating:
“Research overwhelmingly supports the notion that ditching the “three square meals a day” approach in favor of time-restricted eating (also referred to as intermittent fasting) can do wonders for your health, as your body simply cannot function optimally when there’s a continuous supply of calories coming in. The cycling of feasting (feeding) and famine (fasting) mimics the eating habits of our ancestors and restores your body to a more natural state that allows a whole host of biochemical benefits to occur. It’s a powerful approach that not only facilitates weight loss, but also helps reduce your risk of chronic diseases like Type 2 diabetes, heart disease, cancer and Alzheimer’s. While there are many variations, time-restricted eating typically involves not eating for at least 14 consecutive hours a day. However, not eating for 16 to 20 hours is likely closer to a metabolic ideal. This means you eat all of your meals for the day within a four- to eight-hour window. Among the many benefits of time-restricted eating is the upregulation of autophagy and mitophagy — natural cleansing processes necessary for optimal cellular renewal and function. In a January 2020 review paper,1 researchers explain how caloric restriction helps combat Alzheimer’s specifically, through these autophagy pathways.
Preventing Alzheimer’s Through Time-Restricted Eating
As explained in “The Effects of Caloric Restriction and Its Mimetics in Alzheimer’s Disease Through Autophagy Pathways,” two of the pathology hallmarks of Alzheimer’s are amyloid beta plaques and neurofibrillary tangles formed by aggregates of tau protein. “The aberrant accumulation of these misfolded and aggregated proteins results in neurotoxicity, and AD is therefore recognized as a proteinopathy,” the paper states. Other pathological events frequently seen in the brains of Alzheimer’s patients include:
• Synaptic deficits and axonal degeneration
• Mitochondrial dysfunction
• Abnormal metal homeostasis
• Oxidative stress
Many of these occur as a result of “insufficient elimination of neurotoxic proteins or damaged intracellular organelles,” the paper notes. In other words, they occur when there’s insufficient autophagy occurring in your body. The good news is you can upregulate autophagy, and one of the simplest ways is by implementing time-restricted eating. As explained in this review:4 “Autophagy is a catabolic mechanism that ensures the removal of misfolded or aggregated proteins and maintains the turnover of cytoplasmic components. Under conditions of starvation or energy deficiency, phagophores are synthesized de novo in the cytoplasm from newly synthesized lipids or from intracellular organelles with membrane structures, such as the endoplasmic reticulum. Phagophores elongate and curve to form double-membrane autophagosomes, which then encapsulate cytosolic materials, misfolded proteins, or long-lived proteins. After fusion with lysosomes, any cargo is degraded by lysosomal enzymes. The autophagic process provides a strategy for clearing misfolded or aggregated proteins in proteinopathic disorders. Failure of autophagy leads to the accumulation of aggregates, which results in neurotoxicity and disease progression.”
Autophagy Dysfunction in Neurodegenerative Disorders
Autophagy dysfunction has been identified in several neurodegenerative and neuropsychiatric disorders and diseases, including Alzheimer’s, Parkinson’s, amyotrophic lateral sclerosis (ALS), Huntington’s disease, ischemic stroke, schizophrenia and even drug addiction. Hence, it is believed that autophagy activation has an important role to play in the prevention and treatment of these conditions. Importantly though, using autophagy stimulators such as drugs, gene therapy or supplements can have undesirable side effects in some people, and may not be ideal. Time-restricted eating, or calorie restriction, the authors note, is a safer and likely more effective strategy for most. So, just how does calorie restriction or intermittent fasting induce autophagy? There are several mechanisms at play, but two important ones are activation of monophosphate-activated protein kinase (AMPK) and inhibition of the mammalian target of rapamycin (mTOR) pathway. Calorie restriction also helps ameliorate Alzheimer’s and other degenerative conditions by lowering inflammation and improving insulin sensitivity, mitochondrial function and oxidative stress. … One of the reasons time-restricted eating works so well is because you’re cycling through autophagy on a daily basis (opposed to only occasionally, were you to do longer fasts once a month or quarterly, for example).
This cycling is really crucial. You don’t want to inhibit mTOR and activate autophagy all the time. There needs to be a balance between breaking down and building back up. When you eat, your insulin goes up, mTOR is activated and autophagy is inhibited, thus allowing for cellular rebuilding and growth. Then, when you fast, insulin goes down, mTOR is inhibited and autophagy activated, thus allowing for the breakdown and elimination of dysfunctional cellular components. The next time you eat, the cycle of rebuilding begins anew, and so on. When you’re continuously eating, autophagy will be severely inhibited. As a result, damage continues to build up as damaged cells cannot be efficiently eliminated and regenerated. Many hormonal shifts also occur during fasting, including growth hormone. Opinions about how long one should fast each day varies. As a general rule, the recommended range is between 12 and 18 hours of fasting each day. I’m of the opinion that 16 to 18 hours of fasting might be the sweet spot, as this allows your body to deplete the glycogen stores in your liver more and suppress mTOR and activate autophagy better.”
As always this is not offered as medical or health advise. Anyone serious about trying this out needs to consult with their doctor. I do not know how diabetics would go with this, for example. However, it is highly likely that a return to the famine and feast mode of living will be humanities’ future fate, so best to be first in line in the evolution stakes.