Recently, there has been a renewed interest in the keto diet, as we are becoming ever more conscious of the things we eat. The keto diet, which is short for ketogenic diet, has a long history in human dieting. Starting from at least 500 B.C., humans have used diets, similar to that of the keto diet, as a way to treat epilepsy, but today, the keto diet is widely sought after for its reported success in helping people lose weight. 

The defining feature of the keto diet is to have a large amount (around 70 percent) of your daily nutrition coming from fats, while carbohydrates and proteins make up your remaining calories. Normally, your body uses glucose, or carbohydrates, as its main source of fuel; since the keto diet provides a miniscule amount of carbohydrates, it instead forces the body to use stored fat as fuel. 

While this may sound like a great way to lose weight, particularly stored fat, there could be some risks associated with the keto diet, as not enough research has been done on its long-term effects. One of these risks is the chance to develop cardiovascular diseases, specifically atherosclerosis. Atherosclerosis is defined by the buildup of plaque inside arteries, which could eventually lead to heart attacks and strokes. Being on the keto diet changes the levels of some of the biomarkers in our bodies associated with developing atherosclerosis. This article will be focused on two of the biomarkers, namely small-dense low-density lipoproteins (sdLDL) and apolipoprotein B (apoB). 

To understand what sdLDL particles are, we first must understand the types of lipoprotein molecules present in our bodies. There are two main classes of these lipoproteins, which are commonly referred to as low-density lipoproteins (LDL) and high-density lipoproteins (HDL), bad cholesterol and good cholesterol, respectively. In general, we want the LDL levels in our body to be low to prevent plaque build up in the arteries, which leads to atherosclerosis. 

One small subgroup of LDL particles are sdLDL particles, which are the smallest type of LDL particles. A recent study has shown that among all LDL particles present in our body, sdLDL particles have the greatest potential of causing atherosclerosis. This is because circulating sdLDL particles undergo many changes in blood plasma, such as oxidation, that increase its atherogenicity. Thus, it is especially crucial that we keep track of our sdLDL particle levels to ensure that we aren’t at a high risk for atheroscleoritc diseases.

Now, let’s talk about apoB. ApoB is a protein found on the surfaces of lipoproteins, such as sdLDL. ApoB works with lipoproteins to cause atherosclerosis by providing structural integrity for lipoproteins, while also helping to facilitate the transport of lipoproteins into arteries. Because of the cooperative nature between apoB and lipoproteins, studies have accepted that apoB-containing lipoproteins are the greatest causal factor for atherosclerotic diseases. 

So, how does this all relate to the keto diet? 

Studies have shown that sdLDL particle levels and apoB-containing lipoprotein levels change for people once they start the keto diet. However, there is still ongoing debate over whether these level changes are good for one’s overall health. 

On one hand, the keto diet has been shown to yield successful results for diabetic patients. Specifically, the keto diet lowers sdLDL particle levels, while also increasing HDL levels and maintaining constant apoB levels. Because overall LDL levels increase, but apoB levels stay constant, it can be concluded that these new lipoproteins being produced have been transformed in a favorable way. However, these positive effects do vary from person to person based on the sources of fats they consume and the way their body reacts to the dietary restrictions of the keto diet.

Conversely, there has also been research showing that apoB levels actually rise once individuals start the keto diet due to the larger intake of fatty foods. This means that the keto diet may actually be increasing one’s risk for developing atherscleoritic diseases.

The bottom line is that there is still much to learn about the long-term health effects of the keto diet. It is only in recent years that the keto diet has resurfaced in a popular craze, and thus, it will be many more years before we truly understand whether this diet has real merit. But for the time being, whether you are interested in the keto diet or not, it is always best to do your own research beforehand to determine the diet that is best for you.