How Does the Ketogenic Diet Impact Your Cholesterol Panel?
How Does the Ketogenic Diet Impact Your Cholesterol Panel?
One of the most common questions I’ve been asked to address is whether or not a Ketogenic Diet will cause you to develop high cholesterol. The other version of that questions is, “if I have a personal history or family history of high cholesterol, can I still follow a Ketogenic Diet?” While the answer to these questions may be somewhat individually specific, I’d like to shed some of the more generalizable information on how the Ketogenic Diet interacts with your lipid profile (cholesterol). So make sure to read this whole Medical Monday blog post to get the truth behind keto and cholesterol.
To start, it is important to know that roughly 80% of all cholesterol in the body is actually made by the body itself and is not influenced by the intake of dietary fat. With that said, let’s talk about the different components of a cholesterol panel, as they each make answering the earlier questions a bit easier and certainly more significant.
Firstly, you have triglycerides. Triglycerides actually come from dietary intake of carbohydrates that break down as sugar and are converted into their stored form in the body. Belly fat is a great example of this and actually contributes to insulin resistance seen in diabetic and pre-diabetic individuals. Eating a low fat diet will NEVER help you to lower your triglycerides because you’ll likely be eating more of your calories from carbs... which is where triglycerides come from. Additionally, triglycerides have a negative impact on your good cholesterol (HDL) and cause it to lower in concentration in the body.
Next, you have HDL (high density lipoprotein). This is considered your “good” cholesterol because studies have shown that individuals with a greater concentration of HDL have a lower incidence of heart disease and stroke. Additionally, HDL aids in the lowering of LDL (low density lipoprotein) and is seen to be somewhat cardio-protective.
LDL is considered your “bad” cholesterol as it is the type of lipid associated with coronary atherosclerosis (blockages in the arteries of the heart). However, this is not the whole picture. Aside from the fact that this lipid only sticks to the vessel wall because of pre-existing vessel injury, not all LDL is created equal. Further investigation into the breakdown of different types of cholesterol has shown us that LDL is divided into both small particle and large particle LDL. The small particles are actually the only ones associated with heart disease, whereas the large particles have been shown to have next to no association at all with heart disease. Unfortunately, the only way to know which one is elevated is by ordering a more specific and more expensive lab assay that differentiates particle sizes. Because most insurance companies don’t cover this type of testing, it is rarely ever ordered... even amongst cardiology groups.
So what do I, as a cardiology provider, look at when evaluating the lipid profile? This is mostly dependent on the patient’s overall health profile. Co-morbidities (secondary health conditions) such as hypertension, high triglycerides, pre-diabetes/diabetes, obesity, and metabolic syndrome are all likely to draw more of my attention away from the simple LDL lab and may draw my attention more towards the triglycerides and the hemoglobin A1c (diabetic control lab). I would certainly not ignore the LDL, but I may consider adding a more specific lipid panel to evaluate particle size and even evaluating LP(a) which strongly associated with congenital risk for coronary artery disease.
If the individual does not have any of these conditions, particularly diabetes or metabolic syndrome, my focus may be on the LDL and other risk factors. If their LDL is elevated, it does not mean I wouldn’t consider a Ketogenic Diet safe. However, establishing a baseline of their LDL particle size concentrations would be beneficial in making sure this way of eating is safe long term for such an individual.
You may be wondering, given some of the above statements, “Can you really put equal or greater importance on something like triglycerides or diabetic control than LDL?!” To that I would say, absolutely! I have had far too many patients with “perfect” LDL control (an LDL of less than 70) who continue to have progressive coronary artery disease. And what do I see with nearly all of them? Poorly controlled diabetes, severely elevated triglycerides, obesity, and often also poorly controlled hypertension. We love to blame LDL for everything in Cardiology, but the truth is, LDL really isn’t the issue. Certainly not the whole issue. The analogy I make is that blaming LDL for heart disease is like blaming an EMT for killing a patient that he was attempting to resuscitate. If the patient had no pulse, it doesn't matter if the EMT's compressions weren't perfect or breaths weren't all given on time. The bottom line is the patient was already dead; his efforts to save the patient just weren't enough.
LDL actually acts similar to a first responder in that it sees an issue in the vessel wall and tries to fix it. However, the disruption of the vessel wall is the real problem, and often the one that never gets addressed. These disruptions are often the result of uncontrolled hypertension, uncontrolled diabetes, and frequently elevated stress/cortisol levels. These cause stretching and tearing of the vessel wall, platelets float by and are triggered as part of an inflammatory response, and they help the small particle LDLs to sneak into the vessel wall and stick there to close it up. These eventually get bigger as more of these particles and platelets float by and stick on, causing the plaque to expand. So just as the EMT didn’t kill the guy, nor did the LDL. The damage to the vessel wall did.
With my seemingly abstract analogy out of the way, where does keto come in with all of this? Well firstly, consider the fact that the whole premise of the Ketogenic Diet is to restrict dietary carbohydrates and obtain the majority of calories from dietary fat. This means that you’re not eating the carbohydrates that would elevate your triglycerides and blood sugar and you will actually see these numbers goes down significantly (along with body fat percentage, average blood glucose levels, and basal insulin levels). Additionally, because you’re now metabolizing fats for energy in place of carbohydrates, you will actually begin to burn off your cholesterol. This is especially important for individuals who have a genetic predisposition to having high levels of cholesterol in the blood. Lastly, when evaluations of the lipid profile were performed in controlled trials utilizing the Ketogenic Diet as a weight loss or diabetes control intervention, individuals were observed to have drastic reductions in triglycerides, small particle LDL, and a positive increase in HDL. Some individuals did notice a small increase in large particle LDL, but it’s important to keep in mind that this type of cholesterol is in no way considered to be associated with heart disease or increased risk for stroke. The individuals with the elevation in total LDL (broken down as an elevation of large particle LDL), have been deemed "hyper-responders" in discussion around LDL and the Ketogenic Diet. We may talk a little more about this in a future blog post.
So what does this all mean? Can we all do a Ketogenic Diet safely? The answer is that the majority of individuals can. However, I would suggest that you include your healthcare provider in the implementation of this diet and discuss with them your reasons for pursuing a Ketogenic lifestyle. Many people with high cholesterol, though not all, also have other pre-existing health conditions such as high blood pressure, diabetes, or obesity and may need medication doses adjusted as they enter ketosis and begin to lose weight. Having your healthcare provider involved will make it easier and safer to follow this way of life!
Before I wrap things up, I'd like to make one more important point by drawing a comparison between the Ketogenic Diet and the Low Cholesterol diet which is typically what cardiology programs recommend to their patients. In a number of studies looking at the use of the Ketogenic Diet for weight loss and diabetic control in comparison to a Low Fat (cholesterol) diet, and even in some of the epileptic studies, one of the main parameters that was constantly monitored was the patients' lipid panels. The researches were evaluating changes in the lipid panel usually every 6 to 8 weeks to make sure there were not potentially harmful changes that may put the patient at an increased risk of heart attack or stroke. Thankfully, we can reference this information to determine what the typical impact on risk factor control may be when comparing these two diets. In every single one of these studies, there was a consistent reduction of triglycerides noted in the ketogenic group that was never seen in the low cholesterol group. The reason for this was mentioned earlier and has to do with the calorie source. If you're eating carbs, you're eating what will be turned into triglycerides for storage. Another interesting observation was that participants in the ketogenic group had a better improvement in the HDL (good cholesterol) when compared the the low cholesterol group, although some studies did show modest improvement in HDL amongst low cholesterol participants. What of the most interesting observations, however, is regarding the LDL changes. In the vast majorities of studies comparing the Very Low Carb Ketogenic Diet to the Low Cholesterol Diet, both groups had similar reductions in total LDL concentration. However, when particle size was evaluated, the Ketogenic Diet group almost always had a better reduction in small particle LDL (the one associated with heart disease and stroke) while occasionally having a small bump in large particle LDL (no association with heart disease or stroke). This is especially interesting because you can then begin to argue that, regardless of the change in total LDL, the Ketogenic Diet is showing even better control of ALL risk factors for coronary artery disease and stroke than the diet we've been putting patients on for decades!
So if the research is there to support his, why haven't we changed things and why aren't healthcare providers discussing this way of eating? Well I hate to say it but there's a lot of money to be made in the sugar industry and not a whole heck of a lot in just eating healthy. While that shouldn't affect healthcare providers, it may affect the information they are being taught in school and while obtaining continuing education credits during their years of practice. Additionally, this would mean a number of organizations admitting they've been wrong for almost 50 years and admitting that they may have caused harm to our society. Finally, you have to know that your patient is going to be willing and able to make a sustainable change in their lifestyle. For most people, giving up simple carbohydrates is difficult. It can be costly if you don't know how to be frugal when shopping, you may have limited access to some of the more "specialty" ingredients used in some ketogenic recipes, you may not be a good cook and rely on ready-made meals, or you just may not want to give up foods you've been eating and enjoying your whole life... regardless of the negative impact on your health. For the same reasons people struggle to quit smoking, they struggle to change lifestyle habits such as their diet. So most providers aren't willing to spend an hour or more of their already overly sought after office hours with a patient that will not do anything with the information they're given. It's a bit harsh when you hear it like that, but that is the unfortunate truth. Additionally, many healthcare providers still don't know this is the case. While the research has reflected this for well over a decade, many changes to recommendations can take anywhere from 7 to 20+ years to implement into practice. Without proper funding and dissemination of knowledge, some necessary changes to medical practice never make it.
With all of that said, the last thing I'd like to discuss in wrapping all of this up is dietary compliance. While you may find a lot of information about successful weight-loss with a simple Low Carb diet or with "Lazy Keto", this dietary intervention isn't just about losing weight. While healthy and sustainable weight loss is a wonderful side effect of this lifestyle, there is so much more to be gained from it. Additionally, improper implementation of this lifestyle may impair your ability to maintain a constant state of metabolic ketosis, therefore making most of the benefits I discuss above null and void. Adhering to this diet strictly will help to make sure you get the most out of it, will ensure safety, and will make controlling existing co-morbidities (such as diabetes, hypertension, and other medical conditions) much easier. So while it may be okay to have a rare cheat meal, your goal should be to maintain a fairly constant state of ketosis - even if your goal isn't to lose weight.
I hope you’ve found this post helpful. I am frequently asked about the ketogenic diet and how it influences your cholesterol and risk for heart disease so I wanted to use this platform to make sure people were getting the right information.
Remember, this blog does not constitute medical advice and, while I am a board certified healthcare provider, I am not your healthcare provider. Therefore, anything stated herein should be taken as medical information and used to prompt discussion and research with our own healthcare provider. So when making any dietary changes, please include your healthcare provider so it can be does safely and sustainably! And until next time, Keto On!
- Eric Cameron, BSN, RN, MSN, APRN, FNP-C
Cardiology Nurse Practitioner