The 16 8 Diet Explained

Why the 16 8 Diet works, how keto and fasting are linked, and how to do it.

intermittent fasting hours

What is the 16 8 diet and how can it help you live longer?

The 16 8 diet is a popular form of Intermittent Fasting (IF) that is sometimes also called Time Restricted Feeding (TRF).

This diet has quickly gained popularity in the last five years and scientific study is beginning to indicate that it is more than a fad. Human and animal trails of the 16 8 diet show early indications that it is an effective tool for weight loss, can help reduce the risk of heart disease and some cancers, is a treatment option Type 2 diabetes, and can improve brain function. Each of these outcomes are defences against major diseases of aging and can help you to live longer and live better.  

While the 16 8 diet is a version of Intermittent Fasting, it has some major lifestyle benefits not available with other kinds of IF. The 16 8 diet does not require you to fast for long periods and does not impose severe calorie restrictions. Instead, it closely mimics your Circadian rhythm by prescribing that you eat for eight hours in every 24-hour cycle and observe a 16-hour fasting window.

Most people choose to have their eating window during daylight hours; from 10am-6pm or 12pm-8pm, allowing them to keep eating two regular meals each day and snacks in between. Relatively recent evidence points to an increase in effectiveness of the 16 8 diet when the eating window is located earlier in the day, for example from 8am-4pm.

Keto and Intermittent Fasting

Keto is shorthand for Ketosis – a process that is triggered by food deprivation. Researchers have discovered that Keto is a major reason that Intermittent Fasting interventions like the 16 8 diet have such wide-ranging health benefits.

Keto involves what experts call a metabolic switch, which occurs when the body isn’t provided with food.

When not in Ketosis, the body uses glucose from food for energy, but when ketosis occurs the body changes and begins converting stored fat into ketones, which become its energy source.

This results in weight loss as fat is burned off, but researchers – like those who conducted this 2017 study on “The impact of intermittent fasting on health and disease processes” –  say food deprivation also triggers “adaptive responses of the brain and autonomic nervous system” that “play major roles in the fitness-promoting and disease-allaying effects of IF”.

These adaptive changes lead to health improvements like decreases in inflammation, reduction in cholesterol levels, and lower blood sugar levels.

The 16 8 diet is one Intermittent Fasting keto schedule that can induce a metabolic switch and help you enhance your longevity.

How to follow the 16 8 diet

If you want to try keto and fasting, experimenting with the 16 8 diet is an excellent place to start.

To induce Intermittent Fasting Keto, researchers have determined most people need to fast for 8-12 hours, after which the level of ketones in the blood will begin to rise. The 16 8 diet creates a daily fasting window of 16 hours, meaning the body will be in a state of ketosis for 4-8 hours in each 24-hour period.

Before beginning the 16 8 diet it is important to talk to your doctor as your medication or individual nutrition and energy needs could make it inappropriate for you. If you are cleared to try Keto and Intermittent Fasting, then look at your normal schedule of meals and determine which eight-hour eating window will result in the least disruption to your routine. For example, if you normally eat between 8am and 8pm, you could consider swapping to eating between midday and 8pm, so you can still eat dinner with your family.

During the eating window, you can eat any food you like, but experts say the 16 8 Diet works best when paired with healthy food choices such as the Mediterranean Diet.

If you are having trouble making the change to eating only eight hours each day, try phasing the change in gradually. Start with a ten-hour daily eating window. After two weeks of transition, narrow the window down to eight hours. Many proponents of the 16/8 diet and Intermittent Fasting say their bodies eventually adapted to eating only during a four-hour daily window.