Westman’s research on carb-restricted diets suggests they can help reduce appetite, spur weight loss and improve markers of heart disease. His findings aren’t outliers. From Atkins and South Beach to Mediterranean and Zone, low-carb, high-fat diets—or “LCHF” plans—are all the rage, and growing evidence suggests they’re a big improvement on the typical carb-heavy American diet. But the “keto” diet is the most carb-restrictive member of the LCHF gang.
Although the ketogenic diet has been around for a long time and may be efficacious in many medical conditions, there is a surprising dearth of long-term studies on its safety. The bulk of the information comes from children using a ketogenic diet for epilepsy. Negative effects seen in children on a ketogenic diet long-term (≥2 years) are poor growth (while on the diet), kidney stones, and dyslipidemia (elevated cholesterol and/or triglycerides). Many of these effects can be overcome with careful attention to mineral intake while on the diet and/or termination of the diet.52 Most long-term studies evaluating adults using a ketogenic diet for weight loss have found very few serious adverse effects.53 54 55 56 However it should be noted that these studies only looked at one year duration on the diet, and poor adherence to the diet was frequently noted as a problem.
I think it was still hard for him to accept that many cancer patients, and many humans without cancer, did best on a plant-based, high carb diet, so foreign to his way of thinking. Though he had heard me expound on the Kelley approach many times over the years, it was to him implausible that humans as a species had adopted to a variety of diets, some high fat, some high carb, some more balanced, and that in medical practice, we as physicians had to be aware that different patients might require completely different diets for optimal health.
Consistency of meal preparation and consumption is necessary to see optimal effective seizure control. You should receive training on the proper principles of ketogenic meal preparation. Depending on the type of ketogenic diet, your medical team may require that you weigh foods on a scale, or you will be advised to use household measuring utensils.
So far the research has found energy restriction to significantly reduce growth and progression of numerous cancers including mammary, brain, colon, pancreas, lung, and prostate cancer. However, it is important to note that the best results are achieved from severe calorie restriction (<1,000 calories per day). If you are considering using calorie restriction along with your cancer treatment, make sure you consult your cancer care team first.
Here are a few of the most common side effects that I come across when people first start keto. Frequently the issues relate to dehydration or lack of micronutrients (vitamins) in the body. Make sure that you’re drinking enough water (close to a gallon a day) and eating foods with good sources of micronutrients. To read more on micronutrients, click here >
Some experts now feel that impaired energy metabolism may be the defining common factor in nearly all cancers, regardless of their origin.12,14 They believe that cancer, rather than being caused by errors in DNA, is fundamentally a metabolic disease caused by a disruption in a cancer cell’s ability to get the energy it needs from mitochondrial respiration like a normal cell would.
Recommendation: If you are looking to optimize your cholesterol levels and reduce your cardiovascular disease risk, a ketogenic diet that mainly consists of coconut oil, olive oil, avocados, nuts, fish, and animal fats may work best for you. (Still concerned about the recent claims that coconut oil is bad for you? Our article on coconut oil will help clear up the confusion.)

Calorie restriction (CR) and a ketogenic diet (KD) target the same molecular pathways that are also targeted individually by drugs to improve cancer treatment outcomes. Arrows indicate activation, truncated lines inhibition. Carbohydrate (CHO) restriction up-regulates fatty acid oxidation and ketogenesis (beneficial for normal tissues) and impairs glycolysis and glutaminolysis (detrimental to tumor cells). Full study here.

The authors defined a VLCKD as a diet lower in 50g of carbohydrates – lower than the daily recommended grams of carb consumption clinicians recommend to diabetics. They included 13 randomized controlled studies with a total of 1,415 subjects. All studies took place for at least a full year and all subjects included were over 18 years old and had a BMI of at least 27.5 kg/m2. In each of these studies, VLCKD diets were compared to low-fat diets.
In short, a well-formulated ketogenic diet will likely increase your cholesterol. The reason for this is that keto emphasizes a large amount of saturated fat in the diet, and high levels of saturated fat will increase cholesterol. Now, because of Ancel Keys, we’ve be taught that high cholesterol is a problem. However, putting it bluntly, Ancel Keys was wrong. In this meta-analysis of 21 well-formulated studies the conclusion was that there is absolutely no relationship between high levels of cholesterol and heart disease or cardiovascular disease.
In one hypoxia-ischemia model, rats fed a ketogenic diet for 25 days before cardiac arrest had fewer postarrest seizures and myoclonic jerks and less neurodegeneration (determined by Fluoro-Jade staining) than those fed a normal diet [28,29]. The ketogenic diet also appears to have cardioprotective properties in an isolated heart perfusion model designed to mimic global ischemia. These changes were concomitant with increased numbers of mitochondria in cardiac muscle, suggesting that improved capacity to generate energy conferred a protective effect in the face of an ischemic insult [30].
Mitochondria generate reactive oxygen species (ROS) during their metabolic activities. In normal cells, the production of ROS and their elimination by antioxidants are kept in balance.10 Intriguingly, a higher incidence of errors, or mutations, in mitochondrial DNA have been observed in many human cancers, likely as a result of uncontrolled ROS production and oxidative stress.11
Thank you very much, Betsy, for mentioning Dr. Gonzales and his views on the ketogenic diet. We had not heard of Dr. Gonzales before this. In preparing for our reply to you, we found your and your husband Bruce’s website dedicated to healing and restoring personal relationships. We mention this because we do not recall ever receiving a comment from anyone other than health care professionals or people concerned about their own nutrition.

The role of gut microbiota has recently been studied for its effect on several diseases, especially those with some inflammatory involvement. Several metabolic pathways are known to be modulated by the gut microbiota. Olson et al. (2018) demonstrated the impact of gut microbiota on the anti-seizure effect of KD. She found that KD modifies the gut microbiota, with a decrease in alpha-diversity and increases in the putatively beneficial bacteria Akkermansia muciniphila and Parabacteroides spp. This microbiota transformation leads to changes in the colonic luminal metabolome, with a decrease in gamma-glutamyl amino acids. This increases the GABA/glutamate content in the brain by decreasing gamma-glutamyl amino acids in the blood (Olson et al., 2018). In an acute electroshock model, it is reported that KD confers protection against seizures. Moreover, KD decreases the frequency of spontaneous seizures in Kcna1 knockout mice (Kim et al., 2015). In summary, changes in the gut microbiota seem to be important for the KD-mediated seizure protection.
Following a very high-fat diet may be challenging to maintain. Possible symptoms of extreme carbohydrate restriction that may last days to weeks include hunger, fatigue, low mood, irritability, constipation, headaches, and brain “fog.” Though these uncomfortable feelings may subside, staying satisfied with the limited variety of foods available and being restricted from otherwise enjoyable foods like a crunchy apple or creamy sweet potato may present new challenges.
The cancer industry is probably the most prosperous business in the United States. In 2014, there will be an estimated 1,665,540 new cancer cases diagnosed and 585,720 cancer deaths in the US. $6 billion of tax-payer funds are cycled through various federal agencies for cancer research, such as the National Cancer Institute (NCI). The NCI states that the medical costs of cancer care are $125 billion, with a projected 39 percent increase to $173 billion by 2020.
The traditional Atkins’ Diet was certainly high fat, in the range of 70% or more, nearly all from animal sources, and with minimal dietary carbs, less than 10%. Dr. Atkins, famed for his all-encompassing emphasis on ketosis during his early years as a diet doctor, insisted his patients routinely check the levels of ketone bodies in their urine several times a day, using special “ketone strips.”
When she first consulted with Dr. Kelley in 1977 she was in a near terminal state after having failed intensive chemotherapy. Nonetheless, despite her dire situation within a year she had experienced complete regression of her extensive bony lesions, as documented by x-ray studies. Though in subsequent years her compliance with her nutritional regimen would waver and her disease would in turn recur, invariably when she resumed Kelley’s treatment the myeloma would go into remission.
The ketogenic diet has been shown to produce beneficial metabolic changes in the short-term. Along with weight loss, health parameters associated with carrying excess weight have improved, such as insulin resistance, high blood pressure, and elevated cholesterol and triglycerides. [2,7] There is also growing interest in the use of low-carbohydrate diets, including the ketogenic diet, for type 2 diabetes. Several theories exist as to why the ketogenic diet promotes weight loss, though they have not been consistently shown in research: [2,8,9]
In terms of seizure recurrence among children, the risk of seizures returning in those who are seizure free and stop the diet is 15 to 20%, according to Kossoff. In children who experience less frequent seizures, but are not seizure free, about one-third will have some worsening of seizures when the diet is stopped, though this is sometimes transient.
Duchess was diagnosed with cancer in her right anal gland. When the cancer was removed it had spread to her left anal gland and was attached to her bowels. She was given 3 months to live. Since then I have had 2 vets check her glands and have had complete physical. She has a clean bill of health. I am so grateful to you. We are going to start on a maintenance program. I tell everyone how she has done. Thanks
Then there are some more experimental drugs that restrict the availability of glucose via inhibition of glycolysis and other processes. One of those drugs is called 2-DG, and that’s shown quite a bit of promise, so there’s not a lot of research on it yet, and then there’s an older drug named DCA, which also limits the availability of glucose. That has shown some promise, although it has known toxicity and side effects. It may not be a good choice for that reason.
Like any trendy diet worth its balanced portion of salt, the keto diet is said to hold transformative powers. Proponents say it can help people lose weight, improve mood and experience fewer epileptic seizures. For the most part, the science seems to back these claims up — though, to be sure, it's not completely understood how exactly the keto diet affects mood (particularly depression), despite anecdotal evidence the diet might lead to clearer thinking and fewer symptoms of depression.
Failing to consume enough calories on a keto diet can cause fatigue and insomnia, while an insufficient protein intake promotes weight gain and muscle loss. When you first begin a keto diet, it can be helpful to track your food intake with an app such as Carb Manager Keto Diet App; this will allow you to visualize your macronutrient intake and ensure that you don’t undereat calories or protein. As I mentioned earlier, a low-protein intake is not required to obtain the benefits of keto. A sufficient protein intake (15 to 30 percent of total calories) suppresses hunger and, in most people, does not affect blood ketone levels. (43)

Having said all that, there is tremendous value in short-term ketosis. The natural process of ketosis induced by a 3-5 day water fast or the 5-day ProLon Fasting Mimicking Diet has powerful benefits in the body including autophagy, as well as stem cell activation and regeneration. Learn more about that in my interview with world-renowned scientist and longevity expert Dr Valter Longo here.
Tapping into consumers’ desire to glean the benefits of ketosis right this minute—or in the next 30 minutes—manufacturers have created powders and other supplements that promise you can enjoy your favorite foods and still get into ketosis. These supplements—called exogenous ketones—aren’t necessarily bad, but neither are they a free pass to indulge and then effortlessly shift into ketosis.
The understanding of the mechanisms of action of KD is incomplete; however, some theories have been advanced about how it modifies the neuronal metabolism and excitability in order to reduce the seizure frequency. Possibly, the real mechanism of reduction of cortical hyperexcitability involves multiple factors. Some of the systems involved in seizure reduction are related to metabolic changes in the blood and cerebrospinal fluid (CSF), including a decrease in glucose levels and an increase in KB. The mitochondria function and energy reserve may also play a role in the KD mechanisms, resulting in synapse stabilization and excitatory decrease.
Aggressive tumors typically demonstrate a high glycolytic rate, which results in resistance to radiation therapy and cancer progression via several molecular and physiologic mechanisms. Intriguingly, many of these mechanisms utilize the same molecular pathways that are altered through calorie and/or carbohydrate restriction. Furthermore, poorer prognosis in cancer patients who display a glycolytic phenotype characterized by metabolic alterations, such as obesity and diabetes, is now well established, providing another link between metabolic pathways and cancer progression. We review the possible roles for calorie restriction (CR) and very low carbohydrate ketogenic diets (KDs) in modulating the five R’s of radiotherapy to improve the therapeutic window between tumor control and normal tissue complication probability. Important mechanisms we discuss include (1) improved DNA repair in normal, but not tumor cells; (2) inhibition of tumor cell repopulation through modulation of the PI3K–Akt–mTORC1 pathway downstream of insulin and IGF1; (3) redistribution of normal cells into more radioresistant phases of the cell cycle; (4) normalization of the tumor vasculature by targeting hypoxia-inducible factor-1α downstream of the PI3K–Akt–mTOR pathway; (5) increasing the intrinsic radioresistance of normal cells through ketone bodies but decreasing that of tumor cells by targeting glycolysis. These mechanisms are discussed in the framework of animal and human studies, taking into account the commonalities and differences between CR and KDs. We conclude that CR and KDs may act synergistically with radiation therapy for the treatment of cancer patients and provide some guidelines for implementing these dietary interventions into clinical practice.
Dousing your steak with butter, swigging MCT oil out of the bottle, and putting grass-fed butter and MCT oil into your coffee may be more fat that your body can handle, actually leading to the opposite effect than intended—inflammation. Even on a high-fat diet, too much dietary fat can—and often will—stall fat loss. Dial down that excess dietary fat and include more fiber-rich vegetables, berries, legumes, and non-gluten grains for a healthier, more diverse gut microbiome to keep your weight within a healthy range.
25-30 grams a day is about my max with carbs, which my avocado … when I have avocado, that’s about half of that allotment. I have to be real careful with that. My protein is about 80-100 grams. Doesn’t sound like a lot, I’m 6 foot 3, I’m doing my standing work desk here … 6 foot three in a big guy, 80-100 grams doesn’t sound like a lot but if I go over that I start having that gluconeogenesis kick in, and I can see it on my blood sugar monitor and I can see it on my blood ketone monitor. They go in the wrong direction. You have to be real mindful. Then you’re like, okay you cut the carbs, you moderate the protein, well then what do you eat? Hmm.
Some practitioners have raised the concern that long-term adherence to a ketogenic diet may shift the composition of the microbiota (the beneficial microbes that live in our bodies) in an undesirable direction and may even encourage the overgrowth of ‘bad’ bacteria. These beneficial bacteria feed on prebiotics (such as fiber and resistant starch), both of which are likely to be low in a low-carbohydrate ketogenic diet. Without prebiotics, beneficial bacteria are not able to produce substances like butyrate and other short chain fatty acids that keep the intestinal cells healthy, and long-term disruption of the microbiota can lead to a host of health problems throughout the body. 57 58
In another study that involved mice with brain tumors, administration of 65 to 75 percent of the recommended daily calories helped reduce tumor growth by 35 and 65 percent among two different test groups. Total carb consumption was restricted to 30 grams only.14 A different mice study strictly limited carb consumption to 0.2 percent only, which helped reduce the growth of glucose-fermenting tumors.15
Weight Loss – Part of the resurgence in interest in the ketogenic diet is due to the work of Dr. Atkins and his low-carb diet for weight loss. There is strong evidence to support the use of a ketogenic diet as a weight loss therapy.18 19 People following a low-carb diet tend to lose more weight in the first 3-6 months than those following a more traditional diet.20 Part of the benefit likely comes from the fact that ketogenic diets tend to suppress appetite and lead to a natural decrease in calorie intake.21 But even in studies where participants on a low carb diet ate the same number of calories per day as those on a lowfat diet, significant differences in weight loss were observed.22 This is likely due to the fact that ketosis relies on fat from the diet and body fat to produce ketones for energy.
We know now that plaque formation is a culmination of inflammation at the plaque formation site along with a white blood cell mediated interaction between calcium, cholesterol and other biological substances. In fact, it is thought that cholesterol is actually used by the body as a kind of internal bandage when our arterial lining becomes damaged by inflammation. This means that cholesterol build up in the arteries may actually be a protective mechanism.
The mbg Collective is a curated group of our most trusted wellness advisers. Since 2009, we’ve had the brightest, most passionate, and mission-driven leaders in wellness share their intimate stories and world-class advice. Now, we’re giving you unparalleled access to the people who, alongside mbg, are putting the “WE” back in wellness. Consider them your personal guides, there to support you and sustain you on your journey.
Fortunately, the keto diet has been found to decrease inflammation (which is part of the reason why it can help people who have autoimmune thyroid conditions). [29] However, if you still have high levels of inflammation after following the keto diet, then you may have to address other important variables like your stress levels, sleep quality, and food allergies/sensitivities before your cholesterol levels can rest at healthier levels. (By addressing these variables, you will also decrease your stress levels which may help improve your cholesterol levels even more.)
People suffering from diabetes and taking insulin or oral hypoglycemic agents suffer severe hypoglycemia if the medications are not appropriately adjusted before initiating this diet. The ketogenic diet is contraindicated in patients with pancreatitis, liver failure, disorders of fat metabolism, primary carnitine deficiency, carnitine palmitoyltransferase deficiency, carnitine translocase deficiency, porphyrias, or pyruvate kinase deficiency. People on a ketogenic diet rarely can have a false positive breath alcohol test. Due to ketonemia, acetone in the body can sometimes be reduced to isopropanol by hepatic alcohol dehydrogenase which can give a false positive alcohol breath test result. 
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