It seems that intermittent fasting might be the next new diet craze. There is nary a news feed without some article or video touting the “amazing”, “life-changing”, or “mind-blowing” benefits of regulating the time periods when a person ingests any calorie-containing foods.
But what is the hubbub really all about? Why exactly would a person want to stop eating for half, two-thirds, or even the whole day?
There are a number of potential benefits, the first and perhaps most personal is that intermittent fasting encourages a person to really look at what they are eating. Ensuring that a person gets all the nutrition they need within a certain window requires planning. Just doing this helps to refocus and retrain one’s relationship with food.
Beyond that, science has a few things to say:
1. Intermittent fasting has a beneficial impact on glucose regulation. By reducing the amount of time when a person consumes food, the body becomes more sensitive to insulin. This means that the body is more reactive to insulin and is better capable of insulin signaling, both of which are linked to longevity.
2. Fasting helps to generate ketone bodies which have been shown to increase neuroprotection and resistance to epileptic seizures. This is believed to occur because the body produces more β-hydroxybutyrate during periods of fasting. In fact, intermittent fasting diets have been shown to increase β-hydroxybutyrate two-fold. Neuroprotection is of particular importance to those facing diseases like Alzheimer’s or Parkinson’s disease, but it can also help anyone facing stressful circumstances. Synaptic plasticity, which encourages neuron survival and helps stem cells to produce more neurons, is another neural benefit of intermittent fasting.
3. Tumor growth can be reduced. This happens because tumors feed on carbohydrates, i.e. glucose. When glucose levels are more regulated and lower throughout the day, the tumor does not receive the sustenance it needs to grow.
4. The health-span of the nervous system can be prolonged by altering the basic metabolic and cellular pathways that regulate-life span. During the normal aging process, our body is negatively impacted by genetic and environmental factors. However, when intermittent fasting, these changes are not processed as quickly. This is because energy and oxygen are metabolized differently, likely because the body engages in a wider range of metabolic activities throughout the day. Neurons involved in insulin-like signaling, FoxO transcription factors, sirtuins, and peroxisome proliferator-activated receptors aid the production of antioxidant enzymes, neurotrophic factors, and protein chaperones. These processes help cells to resist disease and deal with stress.
5. Cardiovascular health can be improved. In fact, the cardio benefits are similar [but not the same!] to those gained from exercise. It has been shown that when intermittent fasting, heart rate variability is increased. This means that the heart rate can go up and down. Heart rate variability is a signal of cardiovascular function as it demonstrates the adaptability of the heart. For instance, endurance athletes have a very high heart rate variability. Low levels of heart rate variability are indicative of poor health and can signal future heart failure.
It appears that there is a range of benefits from intermittent fasting, which may warrant trying a new diet. However, as with any diet or exercise plan, it is important to consult with a doctor if you have health concerns. Likewise, be prepared, be educated, and listen to your body.
- Anson, R. M., Guo, Z., de Cabo, R., Iyun, T., Rios, M., Hagepanos, A., … & Mattson, M. P. (2003). Intermittent fasting dissociates beneficial effects of dietary restriction on glucose metabolism and neuronal resistance to injury from calorie intake. Proceedings of the National Academy of Sciences, 100(10), 6216-6220.
- Martin, B., Mattson, M. P., & Maudsley, S. (2006). Caloric restriction and intermittent fasting: two potential diets for successful brain aging. Ageing research reviews, 5(3), 332-353.
- Mattson, M. P., & Wan, R. (2005). Beneficial effects of intermittent fasting and caloric restriction on the cardiovascular and cerebrovascular systems. The Journal of nutritional biochemistry, 16(3), 129-137.