Personally, I have been practicing Intermittent fasting (IF) on and off for the past 12 years and it has really helped me maintain my weight but the main reason I practice IF is for its anti-aging effects.

Here is how it slows down aging and at the end I will outline the easiest way to achieve it (seriously so easy!)

How IF slows down aging

1. Cellular Repair and Autophagy

• During fasting periods, cells enter a state of repair. They remove damaged components through a process called autophagy, which helps clean out cellular debris and malfunctioning proteins that accumulate with age.
• Autophagy reduces oxidative stress and inflammation, two key factors in aging and age-related diseases.

2. Reduction in Oxidative Stress

• Fasting reduces the production of reactive oxygen species (ROS), which are byproducts of metabolism that can damage cells and DNA.
• Lower ROS levels lead to less oxidative stress, which is a major driver of cellular aging.

3. Improved Insulin Sensitivity and Reduced Inflammation

• Intermittent fasting improves insulin sensitivity, lowering the risk of chronic diseases like type 2 diabetes and metabolic syndrome.

• The aging hormone:  Lower levels of insulin during fasting reduce cellular aging markers like advanced glycation end products (AGEs), which are associated with wrinkles and tissue degradation.

• Fasting also reduces levels of pro-inflammatory cytokines, mitigating chronic inflammation that accelerates aging and contributes to conditions like arthritis, cardiovascular disease, and neurodegenerative disorders.

4. Enhanced Mitochondrial Function

• Fasting encourages efficient energy production in cells by enhancing mitochondrial health. Dysfunctional mitochondria are a hallmark of aging and can lead to energy deficits and increased oxidative stress.

5. Hormonal Benefits

• Human growth hormone (HGH) levels increase during fasting. HGH supports tissue repair, muscle maintenance, and metabolic health, all of which decline with age.

6. Activation of Longevity Pathways

• Fasting activates AMPK (adenosine monophosphate-activated protein kinase) and sirtuins, enzymes linked to longevity and stress resistance. These enzymes help regulate energy metabolism, repair DNA, and protect against cellular stress.
• Sirtuins are also involved in improving the efficiency of telomeres, the protective caps on chromosomes that shorten with age.

7. Caloric Restriction Mimicry

• Intermittent fasting mimics the effects of caloric restriction, which has been shown in studies to extend lifespan and delay age-related decline in various organisms.

8. Weight Management

• By regulating weight and reducing visceral fat, intermittent fasting lowers the risk of obesity-related diseases, which can accelerate aging.

 

General caution

Overdoing fasting or using extreme protocols may lead to nutrient deficiencies or stress the body, potentially counteracting its benefits.

 

Special caution for women

Research suggests that intermittent fasting can affect thyroid health, particularly in women, which is why I only recommend women doing fasting 12-14 hours per day.

Fasting can reduce active thyroid hormone (T3) levels while maintaining stable T4 and TSH, which may conserve energy, reduce oxidative stress, and support longevity, but prolonged T3 reduction without sufficient nutrients may harm metabolism.

For some women I also suggest refraining from fasting the week prior to menstruating as this is when energy needs and stress sensitivity are higher. If you find it extra challenging at this time, this recommendation may apply to you.

Women with thyroid concerns should consider consulting a healthcare provider before starting fasting, especially if managing symptoms of hypothyroidism or other hormonal imbalances.

 

Here is how I do it:

I eat dinner around 6pm, no eating post dinner. I go to sleep (normally around 930pm).

All the fasting is occurring while I am asleep. I get up and do my exercise (Pilates, yoga, weight training, light cardio sometimes).

I will then have a shake or smoothie around 730- 8am. This means I fast 13-14 hours most days. This is a very easy way to achieve a good fasting window because you are asleep during most of the fasting. You can move the time around to suit your life. 

How to do it if you are man 

For men I suggest they can do 14-16 hours of fasting, so this would mean eating dinner at 6pm and having your first meal at 8-10am.

  

References

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