Keto vs. Vegan: What’s a Girl to Eat? Part 1: The Ketogenic Diet

I’ve been getting a lot of questions about the ketogenic diet as of late. From casual conversation to inquiries from clients looking to improve health, the keto diet is on everyone’s mind.

And while I’m not getting questions about whether or not vegetarianism is healthy, I am seeing a significant increase in vegetarians in my practice who are wanting to ensure their diets are quality, or who are hoping to minimize and recover from disease using a vegan diet.

Both of these diets are EXCELLENT for some individuals and DISASTROUS for others. This is pretty much the case for any extreme dietary protocol, and both keto and vegan fall into these categories due to the amount of foods they exclude. Let me start this series off with the ketogenic diet.

I’m not going to argue that the ketogenic diet is powerful; it is. It’s extreme nature makes it so. However, keto is a double-edged sword that is being inappropriately skewed based upon the agenda of whoever is bashing or promoting it.

What is positive about the ketogenic diet?

A predominately fat-based, low carbohydrate diet is definitely filling. It also gets people off of most processed food simply because our processed foods tend to be high in carbohydrate. I applaud anything that transitions people off of processed food! However, is it wise to stay there? Is this the best diet there is? Is a ketogenic diet the answer to cancer prevention, diabetes, obesity, and more? Not exactly.

The research is very clear that a ketogenic diet can work fabulously as a treatment for epilepsy; this has been known and utilized for some epileptics for nearly 100 years (although its popularity fell off the face of the earth as soon as the first drugs for epilepsy were developed). The diet was developed as an alternative treatment to fasting, which had been used with some success for epilepsy since Hippocrates’ time but has obvious limitations.

When the modern low carb diet developed with Dr. Robert Atkins in the 70’s, the idea of ketosis as a useful option came back into the public consciousness. Research started back up looking at ketogenic diets for cancer supression, neurological disorders, and more. But up until very recently, there has been no research on the long-term effects of such a plan.

What has the last 40 or so years of research shown us?

YES – ketogenic diets are still useful for epilepsy. Refractory epilepsy and epilepsy which does not respond well to pharmaceutical treatment may be improved with a ketogenic diet. If you have epilepsy, give it a go!

Ketogenic diet research on rodents show inconsistent but potentially promising effects for Alzheimer’s, multiple sclerosis, ALS and other neurodegenerative diseases, but the research is no where close to definitive and it appears that it is most effective in earlier stages of disease. Human studies are so limited at this point that it is unwise to make any claims, however what we know about neurodegenerative diseases and how the brain utilizes fuel coupled with outcomes in animal models makes the topic worth investigating more deeply, for certain. The work of Terry Wahls (Wahls Protocol) and Dale Bredesen are less extreme than a ketogenic diet and show promise for neurodegenerative diseases as well. There are human clinical trials for both plans that show incredible promise for Alzheimer’s and Multiple Sclerosis. I’d look to these protocols before using a ketogenic diet for reasons I’ll get into shortly.

For Diabetes – the ketogenic diet fares better than the standard treatment provided to Americans and may help some individuals get off insulin completely if they suffer from type 2 diabetes. Type 1 diabetes is an autoimmune disease in which the insulin-producing cells in the pancreas are destroyed, so Type 1 Diabetics need to be on insulin for life, but can reduce the amount needed, thus reducing some side effects of insulin treatments, by adopting a low carbohydrate diet. It is quite effective for reversing pre-diabetes as well, but I’ll make the statement that far less extreme measures can achieve the same result.

What are the Concerns of a Ketogenic Diet?

The claim that a ketogenic diet is a great diet for cancer stems from a hypothesis known as the Warburg principle, which states that cancer cells hungrily, greedily feed off of glucose. The idea is then that if we starve the cancer of its fuel, it cannot survive. However, cancer cells are adaptive and have been demonstrated to proliferate and grow to utilize fatty acids and ketones as fuel, so we absolutely cannot make a claim that ketogenic diets are quality cancer treatment diets. It depends upon the type of cancer and how it is reacting to its environment. There are scant case studies of brain tumors shrinking and some interesting animal studies, but to make a claim that the ketogenic diet is a therapeutic diet for cancer is grossly irresponsible. To claim it’s an effective diet to prevent cancer is grasping at straws and completely ignores the wealth of clinical and epidemiological evidence that diets rich in antioxidants and fiber from fruits and vegetables are correlated with reduced risk of nearly all types of cancer.

What troubles me the most is the use of a ketogenic diet for weight loss. This is the most common reason I hear of someone implementing the protocol. While this is likely better than a very low calorie crash diet or fasting in terms of fat loss, some studies show muscle tissue loss greater than a baseline lower calorie diet or higher protein diet. Because the ketogenic diet needs to be modest in protein to stay in ketosis, there is the risk of muscle tissue loss for some individuals. Whether or not you are at risk depends upon your metabolism, gender, activity level, and how much you are eating.

Women especially are susceptible to deleterious outcomes on a ketogenic diet. This has everything to do with hormones and our body’s adamant need to ensure we survive to populate the species. For some women, keto can exacerbate thyroid conditions and disrupt sex hormones, leading to a host of complications that don’t easily return to normal simply by adding carbs back in. Some women find their cortisol levels will not tolerate such an extreme transition; carbohydrate actually serves to blunt cortisol and is especially effective for those who tend to have elevated cortisol levels. These individuals will find that a ketogenic diet makes them irritable, sleepless, and may not lose weight like their friends do. They absolutely should NOT ‘keto harder’ or white-knuckle through it, but rather add some healthy, whole food sources of carbohydrate (think winter squash, potatoes, brown rice, yams, fruit) or transition to a paleo diet rich in vegetables and starchy tubers if they are concerned about blood sugar.

Additionally, ketogenic diets can reduce the body’s levels of selenium (also important for thyroid), antioxidants (important for everything), and vitamin C. At a conference last year, I sat next to a doctor who diagnosed her very first case of scurvy! The patient was on a keto diet for several months and developed a Vitamin C deficiency! Vitamin C, antioxidants, and selenium are all needed to facilitate detoxification of pollutants, plastics, and estrogens and are especially vital to disease prevention through this, and a multitude of other processes. These nutrients are also crucial to a healthy immune system, so if you tend to become ill with seasonal changes, think twice about depriving yourself of nutrients which support healthy immunity. One also must be careful about electrolyte balance with a ketogenic diet. Magnesium and potassium levels can get low, leading to muscle twitches, cramping, hypertension, and in extreme cases, heart palpitations. This is more of a problem for those who are not consuming enough vegetables on their keto diet.

Finally, a ketogenic diet negatively impacts gut flora. In just a matter of days, the populations of the microbiome begin to shift. Long-term ketogenic diets can starve beneficial bacteria species that feed on fiber and specific starches. Based upon rodent studies, it appears that if as the beneficial bacteria starve, they will eat away at the mucosal gut lining of the colon, therby increasing the risk of pathogenic infections, increased intestinal permeability (aka leaky gut), and bacterial dysbiosis. It is unknown if healthy populations can reliably be restored through supplementation and starch reintroduction.

I will say that most of our efforts to ‘repopulate’ bacterial populations that have been extinguished have largely been utter failures. Probiotic supplements are beneficial, but NOT because the supplement is settling into your colon, buying a home and making little bacteria babies. The different ways probiotics benefit the body is a topic for another post.

A special note to those who feel keto may be the answer to their weight problems: I want to reinforce the concept that it isn’t about how much weight you can lose, it’s whether or not you can actually keep it off. A ketogenic diet is certainly a helpful jumpstart, but if you do not learn to transition into a more balanced lifestyle that allows you to enjoy holidays, birthdays, and an evening out with friends, you need to ask yourself if it is something worth doing. Having been in the field of nutrition for over 25 years, I’ve seen the Adkins craze of the 90’s come and go. Everyone was on it, convinced their prayers had been answered. Everyone ended up off it, regaining the weight, and looking for the next best thing. It is damaging to the body and spirit to lose and regain significant amounts of weight, and I expect nearly everyone on the keto craze is going to end up just as those who tried Adkins did 20 years ago. Certainly lower carb will be helpful, but you don’t need to be in ketosis or limit carbohydrates to 50 grams a day to get the benefits you are looking for. Rather than put yourself through that extreme, I encourage you to consider something more sustainable yet equally effective in the long term to meet your goals.

There’s a thorough, extensive summary of my thoughts on a ketogenic diet! I hope it has been helpful for you to suss out whether or not keto is something you should consider for yourself. Next up: the vegan diet; pros and cons! Check it out here.



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