How a 72-hour fast pushes your body into ketosis - Performance Optimal Health (2023)

FAQs

Will a 72 hour fast put me in ketosis? ›

Here's what he got out of it. A 72-hour fast, or fasting for three consecutive days without any food intake, can help your body enter a state of ketosis.

Once the 3 day water fast begins, you will drink only water (and potentially herbal tea or black coffee if you choose) for a full 72 hours. You cannot eat any caloric food or beverages, and most people avoid all artificial sweeteners as well.

Your body may go into ketosis after just 12 hours of not eating, which many people do overnight before they "break fast" with a morning meal. (A midnight snack obviously sabotages this process.)

You'll lose weight

“As you release glycogen, you lose water and that is usually the reason for the rapid weight loss. Losing fat takes more time.” Fasting proponent Fung, however, disagrees and maintains that you could lose 1.5 pounds of fat over a 72-hour period.

Electrolytes: The supplements you'll most likely need to replenish during a fast are not vitamins at all, but electrolytes, substances the body needs to regulate and maintain a number of key bodily functions, and which are depleted through physical activity and fasting.

Try some bone broth soup and well-cooked vegetables as the first meal after a long fast. Another idea is to sip on some broth for an hour, then eat a small first meal. You could also include some apple cider vinegar with lemon water as part of your first meal.

Water fast (24–72 hours)

Most people drink two to three liters of water per day during a water fast. The water fast lasts for 24–72 hours. You should not water fast for longer than this without medical supervision because of health risks.

Testing blood ketone levels with a monitor is the most accurate way to determine whether you're in ketosis.

Magnesium balances blood sugar and immune system functions. Sodium BHB is the star ingredient, inducing ketosis and supplying necessary electrolytes. Calcium and potassium supplement the nutrients your body misses out on without carbs.

What are symptoms of ketosis? ›

Fasting of 72+ hours is also shown to improve the body's response to toxin exposure and stress hormones. 24 to 72 hours: you start producing ketone bodies to fuel your brain, and see an increase in fat loss and autophagy. You also start to see an increase in BDNF which supports brain function.

Foods and drinks that can be even more shocking to your system after a fast include those like a greasy cheeseburger, slice of cake, or soda. Even high-fiber raw produce, nuts, and seeds may be difficult to digest.

Water fasting helps you lose weight quickly. According to studies, you can lose 0.9 kg per day by drinking water in 24 to 72 hours. However, this loss of body mass is only from water, carbs and even muscle mass, not fat.

Fasting for 72 hours is difficult for most people without any medical assistance. The body will also begin breaking down muscle tissue and can start leading to vitamin and mineral deficiencies and digestive issues. And that is what happens if you eat nothing for 3 days.

A first time faster won't reach optimal ketosis until well past the 24-hour mark. Most people are so poorly adapted to burning fat that it can take several months of regular fasting before the body easily enters into ketosis. You have to first reverse the insulin resistance and metabolic syndrome.

Consume 20g or less of net carbs per day on this keto menu plan, not too much protein, lots of fat, drink at least 100 ounces of water per day, get plenty of salt and supplement with potassium and magnesium. Boom, three days later you're in ketosis (which you can measure with your ketostix,) and on your way!

Fasting will cause your body to burn through it's stored glucose and force it to create a new kind of fuel - ketone bodies. But fasting alone won't bring you to the promised land of nutritional ketosis. To reach ketosis in 24 hours, you need to add another element to your game... exercise!