To fast or not to fast?

Fasting in an ancient practice often recommended for weight loss and metabolic health, but an individual supported approach to fasting can achieve optimum results.

Fasting has been part of our culture for thousands of years and is associated with spiritual and physical discipline and well-being. It involves abstaining from food or drink for a period of time and physiologically it can result in a switch from burning energy from food for fuel to burning ketones and fatty acids.

Fasting is also known as time restricted eating in line with circadian patterns (12:12) or when feeding is compressed into fewer hours of the day (16:8). It is also possible to mimic fasting by intermittently reducing caloric intake (a fasting-mimicking diet). The advantage of this approach is that blood sugar levels are to some degree maintained and the body is nourished. Time restricted eating with a focus on feeding in the early part of the day takes the benefits of fasting while working with the natural circadian rhythm so blood sugar is not dysregulated.

During the fasting period the body ceases to sense the input of nutrients, triggering pathways that breakdown fats for fuel and if the fast is sustained, pathways associated with repair and restoration can also be triggered. In some individuals this can reach a positive state of metabolic flexibility (the ability to adapt to the input of different macronutrients for fuel and periods of feeding and fast), improved insulin sensitivity and gut health.

However it is important to realise that, without food, blood glucose levels will fall, and this can result in blood sugar dysregulation, increases in cortisol, hormone imbalance and fatigue. Poor digestion can result from disordered eating patterns and protein loss due can lead to muscular sarcopenia. Therefore for at risk groups, including menopausal females and older individuals, fasting may be a risky approach. Indeed studies have shown that skipping breakfast can contribute to the risk of type 2 diabetes and constipation. Intermittent fasting in menopausal females has been found to contribute to reduced DHEA which can lead to sex hormone dysregulation.

That said, fasting when correctly managed with the help of a nutritional professional can result in the reversal of many of the physiological changes and symptoms associated with type 2 diabetes including weight loss and improved insulin sensitivity. This has been observed in trials of the fasting mimicking diet.

Without the help of a professional fasting risks disordered eating, food fixation and nutrient loss. For many the key to restoring health is nutrient density and fasting can confuse this, therefore fasting is best applied with individual guidance and support.

If you would like to integrate a fasting pattern into your lifestyle and would like some support, contact me directly via the details on this website.

Warm Wishes,

Eleanor

References

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