When we talk about fasting, we usually mean water fasting. In other words, no food.
But there are other types of fasts. Fat fasting is one of them.
Here’s a quick guide to fat fasting – what a fat fast is, who it might benefit, and how it works.
What is a fat fast?
A fat fast is essentially a very low-calorie and very high-fat diet.
You’re fasting from most foods and consuming around 80-90% of your calories from fat.
The length of a fat fast can vary, but most people go anywhere from one day up to a week.
Longer than that is not usually recommended.
The concept was invented by Dr Atkins, also known as the father of modern ketogenic diets.
He recommended it for patients who struggled with high metabolic resistance.
How does eating fat help to lose fat?
It sounds counterintuitive. Eat fat to burn fat? How does that work?
It works in the same way that regular water fasting or the Ketogenic diet works.
Ketones.
Fat fasting helps you make that switch from burning glucose to burning ketones.
And it can help you make that metabolic switch faster.
It’s basically a ramped up version of the Ketogenic diet.
Fat fasting is harder than Keto, but not as challenging as a full water fast.
Who should try a fat fast?
Fat fasting can be very effective in certain situations:
Getting ready for water fasting
If you’ve never done a water fast and you’re anxious about starting, a fat fast can be a gentler way to jump into the fasting lifestyle.
Coming from a high-carbohydrate diet
Cutting out sugars and refined carbs is never easy. These substances are as addictive as class A drugs and many people struggle when trying to break away.
Starting your new low-carb lifestyle with a fat fast can make the transition a bit easier.
Struggling to break into ketosis
If you are on Keto but struggling to break into or stay in ketosis, then a fat fast may be exactly the right solution, devised by Dr Atkins himself for this very purpose.
Getting unstuck
If your weight loss on other types of diet or fast has plateaued, a fat fast can get things moving again.
You want to try something different
Sometimes it’s fun to just change things up!
A fat fast every once in a while can boost your Keto diet, or break up the monotony of water fasting.
What can I eat when I’m fat fasting?
The fat fasting formula is fairly simple.
Aim for high-fat foods and stay away from carbohydrates. You are aiming to get 80-90% of your calories from fat.
Here’s a list of some of the foods you can choose from:
- High-fat meats and fish: High-fat beef, ribeye, pork belly, bacon, salmon, sardines,
- Eggs
- High-fat dairy products: Butter or ghee, heavy whipping cream, high-fat cream cheese, high-fat sour cream, high-fat cheeses
- High-fat oils and spreads: Olive oil, coconut oil, avocado oil, mayonnaise, duck fat, etc.
- High-fat plants like avocados and olives
Foods to avoid:
- All carbohydrates (this means sugars and carbs including breads, pastas, most fruits and vegetables)
- Lean meats (they don’t have enough fat)
- Low-fat options like low-fat creams or low-fat cheeses
Drinks:
Stick to water, tea, or coffee, with no added sugars or sweeteners.
Are there any drawbacks to fat fasting?
Fat fasts are generally safe for most healthy people. (If you have any medical conditions, consult your doctor before changing your diet or lifestyle.)
There are however a few things to be aware of:
Supplements
You obviously won’t be hitting all your nutrient requirements during a fat fast.
You might need to supplement with a good multivitamin.
And as with any fasting or Ketogenic diet, you should supplement your electrolytes.
Can cause tummy issues
Eating all that fat can cause stomach upset. Diarrhea can be a problem for many people.
Keto flu
You might experience Keto flu.
This is much more likely if you normally eat the standard high-carbohydrate diet.
Symptoms can include:
- Nausea
- Body aches and pains
- Cramps
- Headaches
- Brain fog
- Fatigue
Read our article on Combating Keto Flu here: Combating Keto Flu
Not a long term solution
Because fat fasts are very low-calorie and lacking in nutrients, it’s not something you can do every day. Or even every week.
Fat fasting is restrictive, and doing it too often could cause issues with your metabolism.
You may ask, “But isn’t water fasting restrictive?” It’s not the same.
Having no calories (as in water fasting) is not the same as having fewer calories.
Who should not try fat fasting?
Same as with any kind of fasting, some people should not try fat fasting:
- If you are pregnant or breastfeeding
- If you have been diagnosed with an eating disorder
- If you have a low BMI
- If you don’t have a gallbladder you might not be able to do a fat fast
As always, please consult with your doctor before making any changes to your diet, especially if you have any metabolic conditions such as diabetes or heart disease, or if you are on any medications.
Fat fasting can be a good option
Fat fasting is not for the faint hearted, but it works very well in certain situations.
If you’re struggling to transition to a healthier LCHF lifestyle, or if you’re having a weight loss stall, a fat fast might be the answer.
Author: Roo Black
Roo is a fasting coach with over 5 years of experience. She leads the admin team of the Official Fasting for Weight Loss Facebook group – one of the largest fasting communities on social media with over 125,000 members. We highly recommend this group for anyone who is looking for fasting advice or coaching.
