The Keto Diet is all the rage nowadays. I feel like so many of my clients, especially those trying to lose weight, are all on the keto diet band wagon. And to be fair, a number of people I know have been seeing a good amount of success with it.
So, what exactly is a ketogenic diet? The keto diet is a high-fat, low carbohydrate diet that includes an adequate amount of protein. The macronutrient percentages vary between 65-90% fat, 5-25% protein and 4-10% carbohydrates, depending on the person. The idea behind it is that when you substantially limit the intake of carbohydrates, the body will eventually run out of its fuel, or blood sugar (which primarily comes from the breakdown of carbohydrates), and it will look for alternative sources, namely protein and fat. The liver will then convert fat into fatty acids and ketone bodies. These ketone bodies can be used as an alternative fuel source. Elevated levels of ketones in the blood is known as “ketosis.” By limiting the amount of carbohydrates in your diet and remaining in a state of ketosis, the body will break down fat, resulting in weight loss. This diet is not new. It has been around for a long time, however historically it was used to treat epilepsy, primarily in children. More recently, it has become an increasingly more mainstream diet, particularly for weight loss.
The keto diet may be a good option for certain people on a short-term basis, but in general it is not my “go-to” recommendation for most of my clients. First of all, it is a difficult diet to follow. A lot of people find it challenging to eat that much fat on a daily basis and many people just do not feel very well eating so little carbohydrate. Often referred to as the “keto flu,” many people report feeling tired and just not well during their first few weeks on the keto diet. Further, in order for it to work, you need to ensure you are actually in ketosis to get the results that you are looking for, meaning you have to strictly adhere to this diet – no “cheat” days. There are also some negative side effects that can come along with this diet such as constipation, dehydration, electrolyte imbalances and depression. Limiting our daily intake of carbohydrates also means limiting the amount of fiber we eat daily, which can result in constipation – this is particularly difficult for people who may already have issues in this area. When we restrict carbohydrates the body sheds water, as well as electrolytes, which further exacerbates the constipation problem. Therefore, it is key that you make sure you are drinking plenty of water and supplement electrolytes. In general, a strict low carbohydrate diet is contraindicated for people who suffer from depression. Carbohydrates are required for the appropriate absorption of tryptophan, an amino acid which is used to make serotonin. Serotonin, often referred to as the “feel-good” hormone, is a neurotransmitter which is often low in people who suffer from depression. Therefore, people can experience mood changes, especially when starting the keto diet. In addition, serotonin is important for gut mobility and digestion.
Beyond these side effects, if you are dealing with certain health conditions, this diet may not be the best option for you, namely adrenal fatigue and thyroid issues. The adrenals play a crucial role in how we manage stress. Under periods of stress, our adrenals release hormones like cortisol and epinephrine, which increases our breathing rate and heart rate, pumping oxygen and glucose to our muscles so we can escape a threat. This is known as “fight or flight.” This is meant to be a short-term response, however nowadays, people are constantly on the go and under significant daily stress, which long-term wears out our adrenals, also referred to as adrenal fatigue. Therefore, for people who are already suffering from adrenal fatigue, we do not want to add to their stress levels. Further, stress downregulates the thyroid gland.
So how is the keto diet stressful? The mechanism by which the keto diet works is really a “back-up” mechanism for the body, which to be used during times when food is scarce. The body uses glucose, from the breakdown of carbohydrates, as its primary food source. So, from an evolutionary perspective, the body developed a mechanism by which ketones, derived from fats stores, can be used to fuel the body to stave off starvation in times when food is limited. Inherently this mechanism kicks in at a time of stress, therefore it stimulates the increase of cortisol, and is meant to be a short-term solution until food is found. Therefore, this could potentially exacerbate compromised adrenal and thyroid function and for that reason the keto diet may be contraindicated for people with these conditions.