Intermittent fasting and Keto (ketogenic) diets are both popular ways to lose weight. Let’s take a closer look at these two methods of losing weight and see what the benefits and the risks are of each.
What is intermittent fasting?
Intermittent fasting is a way of eating that involves fasting for some amount of time and having a specific time for eating. There are various protocols for intermittent fasting each with a fast time and an eating window. Here are some popular examples:
12/12 means that you don't eat for 12 hours. This would be eating dinner at 6 and having breakfast at 6 the next morning.
16/8 is 16 hours of fasting with 8 hours that you are allowed to eat. This is one of the more popular methods of fasting
20/4 is 20 hours of fasting with 4 hours of eating time. This is one of the more extreme versions of intermittent fasting.
Intermittent fasting technically does not include recommendations for what you should eat, just the timing.
Negative Impacts of Intermittent Fasting
The negative impacts of intermittent fasting likely outweigh the positives. These include:
Loss of muscle mass. There may not be enough time in an IF eating window to allow you to eat enough protein to maintain muscle mass.
Hormone regulation especially in women. This can include reproductive hormones, thyroid hormones, and cortisol. The thyroid hormone imbalances can end up slowing your metabolism. And the high cortisol levels can disrupt your sleep (which makes weigh tloss difficult).
Hunger. Obviously if you do not eat, you will get hungry, this will cause you to over eat when you do come to eat. This also exacerbates bingeing and eating disorders, not to mention an unhealthy obsession with food as you will always be thinking about it and can be tempted easily.
Loss of nutrients and electrolytes. Fasting does not allow your body to get the nutrients it needs when it needs them.
Limited fibre intake
Can lead to cravings. Cravings start due to hunger especially for quick fix starchy, sugary and fatty foods all calorie dense. Your willpower is much reduced and thus the risk of eating allergens such as wheat, gluten and dairy are much higher. This leads to more inflammation, disease and weight/fat gain.
Blood sugar imbalances which can lead to irritability, mood swings and headaches.
Lower energy levels at the end of a fast time. This can make it difficult to make it work with your life. For example, if you exercise in the morning before work you may find you don’t have the energy to do this while fasting.
Doesn’t promote healthy eating patterns. Although you are not restricted in your choice of foods, you are restricted when you eat them. So you ignore hunger signals that your body is providing. Improving your relationship with food is a good place to start.
What is Keto
A ketogenic or Keto diet is a popular weight loss diet. The Keto diet is a high fat, low protein and very low carb diet. The standard Keto diet includes 70% fat, 20% protein and 10% carbohydrates.
Benefits of Keto
The Keto diet does have several benefits, but only in certain circumstances. This diet was originally developed to treat epilepsy in children and it has been shown to reduce seizures in both children and adults. There are also improvements for people with other neurological diseases like Parkinson’s, Autism and bipolar disorder. If you have a neurological condition speak with your physician to determine if this diet is right for you.
Negative Impacts of Keto
Keto is definitely not a 1 size fits all approach. Many issues can arise and it is definitely not a long term solution.
Besides the fact that it is hard to sustain due to symptoms and difficulty making food choices I have found it does not result in long term, sustained weight/fat loss. Instead it causes a slow metabolism, muscle loss and thyroid issues.
Because of the very low carbohydrate amounts in a keto diet, macronutrients must be strictly controlled. This makes it difficult to sustain long term. It also means that your diet will be lacking many key nutrients.
It is impossible to get enough fibre in a Keto diet which can lead to constipation.
With the Keto diet you’ll need to take a number of supplements to try to meet nutritional requirements. This includes fibre, and several vitamins and minerals that could normally be obtained from food. This is a diet that is designed to not even come close to meeting nutritional requirements.
The high fat content of the Keto diet can lead to fatty liver disease, IBS and other gut disorders, gall bladder issues and female hormone imbalances.
I have seen many diets come and go over more than 2 decades of my career. When we go to drastic extremes with diets, whether it’s extremely low fat or, in the case of Keto, extremely low carb, it puts too much stress on the body and serious problems arise.
When a diet like Keto sounds too good to be true, it probably is.
Some other adverse reactions to the Keto diet include:
Mood swings, impaired concentration and cognition
Digestive issues including diarrhea, GERD, vomiting and constipation
Nutrient deficiency. Most of our vitamins come from vegetables and fruit which are severely limited or completely banned on a ketogenic diet.
Keto and intermittent fasting are popular methods for weight loss. But these extreme methods may not be your best choice. Neither method promotes long term results or long term health. To find out more about healthy ways to lose weight, book a free nutrition assessment.
Vicki Witt | Clinical Nutritionist | Holistic Coach | Reiki Master | Certified LEAP allergy therapist Over 25 years of successfully helping you achieve optimal health and weight loss 🍏 | www.vickiwittweightloss.com
Vicki Witt is a Clinical Nutritionist, Holistic Health Coach, and Reiki Master. She has been practicing over 25 years and specializes in holistically customizing diet and lifestyle plans to each individual for weight loss and hormonal control. Her clientele often report they feel the best they have ever felt and wish they had started sooner. One of the USA and Australia's top Nutritionists, she has won multiple awards for her services in the industry.