In recent years, the ketogenic diet has exploded onto the nutrition scene. It is a very strict way of eating that causes the body to enter a state of ‘ketosis’, in which fat is burned as the main source of energy rather than glucose from carbohydrates. In order to achieve this, daily carbohydrate consumption must be restricted to between 20-50 grams, which is a far cry from the average person’s 265 gram/day intake. The diet is also characterised by very high levels of fat consumption, which is usually between 70-90 per cent of daily caloric intake.
Originally, the ketogenic diet was used to help control seizures in children with epilepsy who had not responded to medication, and to this day it is purported for its neuroprotective potential. It is often the prescribed dietary intervention for Alzheimer’s, Dementia and Parkinson’s Disease, and is also used in the management of conditions such as Type 2 Diabetes and PCOS. Whilst the diet’s successes and benefits are well documented, it is, however, not without its downsides. As with all diets, keto is not for everyone, and there are some areas that need to be taken into special consideration. These include:
Increased Exposure to Lipophilic Toxins
Environmental toxins are largely lipophilic, meaning they are often stored in adipose tissue. Some examples are:
- Persistent organic pollutants (POPs)
- Polychlorinated biphenyls (PCBs)
- Organochlorine (OC) pesticides
- Polybrominated flame retardants
- Polybrominated diphenyl ethers (PBDEs)
- Bisphenol-A (BPA)
The risk of the ketogenic diet’s increased fat intake is that food sources that have been contaminated with these toxins will be consumed, thus increasing toxic load on the body. Exposure to lipophilic toxins has been linked to stroke, cognitive disorders, blood sugar dysregulation, obesity, autoimmune disorders, and reproductive disorders.
Whilst it won’t protect from contaminants altogether, it is important to opt for organic meat and wild fish in order to reduce the chance of exposure.
Risk of Metabolic Endotoxemia
Current research demonstrates a link between high fat diets and an increased risk of metabolic endotoxemia. This occurs when gut dysbiosis and the excess of gram-negative bacteria allow high amounts of lipopolysaccharides (endotoxin) into the blood, causing inflammation and thus, chronic illness. It is important to note that the diet pattern included in the majority of these studies is closer to a typical Western style than ketogenic, but with that being said there is emerging research that high levels of even healthy fats may also lead to this condition.
In order to mediate these potential risks, it would be beneficial to firstly focus on healing the gut before loading the diet with consistently high levels of fat. In addition, because ketogenic diets are predisposed to include less fibre, once adhering to this way of eating, it is important to include as much fibre-rich food within the carbohydrate allowance as possible. This, in turn, will feed good bacteria, promoting a healthy gut microbiome and reduce the risk of dysbiosis.
Decreased Dietary Fat Quality
Different types of fat behave differently depending on biochemistry, genes, stress level, and gut microbiome. As fat constitutes between 70 and 90 per cent of caloric intake, when adhering to a ketogenic diet it is important to not focus solely on the quantity of fat consumed without also considering the quality of the sources and the suitability to the individual. Building a diet around fried foods, vegetable oil and dairy just because it may meet the fat quota may increase inflammation in the body, which in turn increase the risk of chronic illnesses.
Reduced Variation in the Diet
The ketogenic diet consists of extensive restrictions on what can and cannot be consumed, and because of this it can be difficult to meet nutrient requirements and incorporate a variety of colourful foods. Fruits and vegetables are primarily made up of carbohydrates, which makes it challenging to consume the recommended 9 to 14 serves of fruits and vegetables per day whilst still complying with the 20-50 gram carbohydrate limit. That being said, with careful planning and an emphasis on consuming as many nutrient dense foods as possible, it can be achieved.