In an era where health and wellness reign supreme, two widely adopted trends, ketogenic dieting and intermittent fasting, have garnered attention for their reported health benefits and weight loss effects. But what happens when you merge these two nutritional strategies?
Welcome to the world of keto intermittent fasting! This dietary approach fuses the high-fat, low-carb regimen of the keto diet with the structured eating periods of intermittent fasting.
Stay tuned as we dive deep into the nitty-gritty of this unique dietary approach so you can determine if it’s right for you.
Understanding the Basics of Keto Intermittent Fasting
First, let’s make sure we understand the two key components that make up this dietary protocol: the keto diet and intermittent fasting.
The Ketogenic Diet
The ketogenic diet, popularly known as “keto,” is a dietary regimen that emphasizes high-fat, adequate-protein, and extremely low-carb intake.
The goal of the diet is to push your body into a state of ketosis, a metabolic process where the body, in the absence of sufficient carbohydrates, begins to burn body fat for energy. The liver converts these fats into molecules called ketones, which serve as an alternative energy source for the brain and other body tissues.
The standard keto diet plan typically involves consuming:
- 60-70% of your calories from fat
- 15-30% from protein
- 5-10% from carbohydrates
Intermittent Fasting
Intermittent fasting, on the other hand, is not a diet in the traditional sense. Rather, it’s an eating pattern that centers around when you eat—not what you eat.
Intermittent fasting cycles between periods of eating and periods of fasting. There are various methods of intermittent fasting, but some of the most popular include:
- The 16/8 Method: 16 hours of fasting followed by an 8-hour eating window.
- The 5:2 Method: Eating normally five days a week and restricting calories to 500-600 the other two days.
- Alternate-Day Fasting: Fasting every other day.
The Benefits of Keto Intermittent Fasting
Keto intermittent fasting combines the principles of the keto diet and intermittent fasting. With this approach, not only are you being very selective about what you eat, but also limiting when you eat.
While these two approaches might seem different on the surface, they are like two peas in a pod. They work toward the same goal of inducing ketosis. As such, they share many wellness benefits. In fact, the keto diet was originally introduced as a dietary means of mimicking fasting.
When these two approaches are combined, they may amplify each other’s benefits. Here are some of the potential benefits associated with keto intermittent fasting:
#1: Accelerated Weight Loss
Independently, both the keto diet and intermittent fasting support weight loss by encouraging the body to enter ketosis.[*][*] When combined, they work synergistically towards the same end goal—improving your body’s ability to burn fat as fuel.
Adding intermittent fasting to a keto diet may make it easier to enter and stay in ketosis. This is because fasting is the quickest route to stimulate your body’s ketone production, as it removes all food (and thus, glucose).
#2: Improved Metabolic Health
Both keto and intermittent fasting have been shown to improve metabolic markers like blood sugar and insulin levels.[*][*] By reducing carbohydrate intake and incorporating fasting periods, your cells may respond better to insulin (become more insulin sensitive).
Insulin is a hormone that regulates blood sugar levels by facilitating glucose uptake by cells for energy. High insulin sensitivity is desirable as it means less insulin is needed to maintain blood sugar control, reducing strain on insulin-producing cells and decreasing the risk of diseases like type 2 diabetes.
#3: Enhanced Brain Function
Both the keto diet and intermittent fasting have been shown to enhance brain function. Keto was first used in a clinical setting as a supporting treatment for epilepsy.[*] The diet has since shown promise for mitigating the risk of other neurological conditions like Parkinson’s and Alzheimer’s disease.[*] Learn more about how a keto diet can boost brain health here.
To add to those brain-boosting benefits, intermittent fasting has been shown to increase the production of brain-derived neurotrophic factor (BDNF).[*] BDNF is a protein that’s been called “Miracle-Gro for your brain.” [*] It supports the survival of existing neurons and encourages the growth of new neurons and synapses. Increased BDNF levels may lead to improved cognitive functioning, learning, and memory.[*]
#4: Autophagy Stimulation
Autophagy is a cellular process in which the body cleans out damaged cells to regenerate newer, healthier ones. Both intermittent fasting and a ketogenic diet have been shown to induce autophagy, leading to improved cellular function and potentially contributing to disease prevention and longevity.[*]
#5: Reduced Inflammation
Chronic inflammation has been called “the root of all disease” by many top health professionals. Fortunately, both the keto diet and intermittent fasting show promise when it comes to reducing inflammation in the body and brain.[*][*]
Potential Downsides and Risks of Keto Intermittent Fasting
While keto intermittent fasting has numerous potential benefits, it also comes with potential downsides and risks that should be considered before embarking on this dietary regimen. These include:
#1: Nutrient Deficiencies
The keto diet and intermittent fasting limit the types and quantity of foods you consume, which can potentially lead to nutrient deficiencies if not carefully managed.
It’s important to ensure you’re consuming all the vitamins and minerals you need, as well as enough calories for your size and activity level. Tracking your food intake using an app like Cronometer can help you determine if you’re hitting your nutritional targets.
#2: Disordered Eating Patterns
In some people, constantly monitoring carbohydrate intake and eating within specific timeframes can create an unhealthy preoccupation with food and potentially exacerbate underlying eating disorders.
#3: Electrolyte Deficiency
While anyone on any diet is vulnerable to electrolyte deficiency, the risk is more pronounced for those following a keto intermittent fasting protocol.
Why? When you eat a very low-carb diet or fast, insulin stays low, which increases the loss of water, sodium, and potassium through urine.[*]
Additionally, most folks who adopt a keto diet reduce their intake of sodium-rich processed foods and some electrolyte-rich foods like legumes and fruits.
Fortunately, this doesn’t need to be a deterrent. Adding a sugar-free electrolyte supplement, such as IQMIX, to your water can help ensure you get the electrolytes you need to feel and function your best. Each packet of IQMIX contains only 10 calories and 3 grams of carbs, which won’t kick you out of ketosis or disrupt your fasting periods.
Is Keto Intermittent Fasting Right for You?
Determining whether keto intermittent fasting is right for you involves careful consideration of several factors. This unique dietary approach is not a one-size-fits-all solution and what works for one person may not work for another. Here are a few things to consider:
- Your current health status: If you have any pre-existing health conditions, it’s essential to discuss the plan with your healthcare provider before making any dietary changes.
- Your lifestyle: Consider your daily routine, work schedule, and other commitments. Does the eating and fasting schedule fit into your day without causing excessive stress?
- Your health and fitness goals: Are you looking to lose body weight, improve your metabolic health, enhance your cognitive function, or all of the above? If so, keto intermittent fasting is worth considering.
A Key Tip for Keto Intermittent Fasting Success
Combining keto with intermittent fasting can be a good approach for many, but starting slow is essential. For beginners, a standard 12-hour overnight fast is a good place to start. This entails fasting for twelve hours overnight from dinner to breakfast (i.e. don’t eat from 7 p.m. to 7 a.m.).
From there, you can slowly increase your fasting window one hour at a time as you see fit. A good goal to aim for is the 16:8 approach, which involves fasting for 16 hours a day and consuming all of your daily food within an eight-hour window (i.e. from 11 a.m. to 7 p.m.).
Embracing keto intermittent fasting, like any lifestyle change, requires both patience and persistence. But with careful planning, balanced choices, and a deep understanding of your body's needs, this approach can be a stepping stone to a healthier, more vibrant you.
Written by Katie Koschalk, a health and wellness writer, certified holistic nutritionist, and certified personal trainer based in California.