While it’s true that low-carb diets do raise the so-called bad LDL-cholesterol in some people, it’s important to note that LDL-C, when influenced by diet, has never been shown to have any effect on cardiovascular risk. Large clinical trials and observational studies show that one’s level of LDL-C and the lowering of LDL-C through diet is not reliably linked to cardiovascular outcomes.21, 22, 23
The final one is the area that I and many others who have pursued a state of ketosis fall into. At this point in my life, I have no chronic diseases, I feel great 99% of the time, but I am always looking to improve my productivity and performance. I have found being in mild-ketosis to be one of the best ways to improve my energy, mental acuity, creativity, physical strength and overall life performance.
The past 4 years I was suffering from mild to severe pain all over my body and unrelenting fatigue, sleep disturbances, brain fog, etc. Diagnosed with Sjogren’s Syndrome and Fibromyalgia. Medication included Vicodin, Morphine and a muscle relaxer. I would not take Plaquenall (spelling?), Lyrica or other “biologics”. I was taking a bunch of supplements but nothing was improving.  
I’m discouraged to see that nowhere in the article nor in the comments is there a mention of a diet’s best fit to genetics. Consider if someone is an APOE E2 carrier and/or has certain polymorphisms of the APO5 gene. These are quite rare in Okinawa but much more prevalent in the USA (12% of the population). According to a number of well-designed studies, these genetic characteristics point to a higher fat, lower carbohydrate diet as beneficial and even a “moderate” carb diet as problematic.
Conklin's fasting therapy was adopted by neurologists in mainstream practice. In 1916, a Dr McMurray wrote to the New York Medical Journal claiming to have successfully treated epilepsy patients with a fast, followed by a starch- and sugar-free diet, since 1912. In 1921, prominent endocrinologist Henry Rawle Geyelin reported his experiences to the American Medical Association convention. He had seen Conklin's success first-hand and had attempted to reproduce the results in 36 of his own patients. He achieved similar results despite only having studied the patients for a short time. Further studies in the 1920s indicated that seizures generally returned after the fast. Charles P. Howland, the parent of one of Conklin's successful patients and a wealthy New York corporate lawyer, gave his brother John Elias Howland a gift of $5,000 to study "the ketosis of starvation". As professor of paediatrics at Johns Hopkins Hospital, John E. Howland used the money to fund research undertaken by neurologist Stanley Cobb and his assistant William G. Lennox.[10]
Our bodies are incredibly adaptive to what you put into it – when you overload it with fats and take away carbohydrates, it will begin to burn ketones as the primary energy source. Optimal ketone levels offer many health, weight loss, physical and mental performance benefits.1There are scientifically-backed studies that show the advantage of a low-carb, ketogenic diet over a low-fat diet. One meta-analysis of low-carbohydrate diets showed a large advantage in weight loss. The New England Journal of Medicine study resulted in almost double the weight loss in a long-term study on ketone inducing diets.
What about fruits and vegetables? All fruits are rich in carbs, but you can have certain fruits (usually berries) in small portions. Vegetables (also rich in carbs) are restricted to leafy greens (such as kale, Swiss chard, spinach), cauliflower, broccoli, Brussels sprouts, asparagus, bell peppers, onions, garlic, mushrooms, cucumber, celery, and summer squashes. A cup of chopped broccoli has about six carbs.
The modified Atkins diet reduces seizure frequency by more than 50% in 43% of patients who try it and by more than 90% in 27% of patients.[18] Few adverse effects have been reported, though cholesterol is increased and the diet has not been studied long term.[48] Although based on a smaller data set (126 adults and children from 11 studies over five centres), these results from 2009 compare favourably with the traditional ketogenic diet.[18]
Here’s the real kicker: the reason why the Inuit don’t go into ketosis as readily as other ethnic groups is the high prevalence of a deleterious mutation in the CPT1A gene.[14] This mutation permitted adaptation to a high fat, low carbohydrate diet in the sense that those carrying the gene could survive to reproductive age while eating a diet entirely at odds with our evolutionary history. However this gene is associated with high infant mortality rates due to hypoketotic hypoglycemia: when Inuit babies’ blood glucose levels drop, they are unable to utilize ketone bodies to sustain their brains. The very mutation that permits adult survival in extreme circumstances compromises infant health – a powerful example of the trade-offs inherent to evolution. Humans can indeed adapt to an extreme environment and an extreme diet, but that adaptation comes at a high cost.

The past 4 years I was suffering from mild to severe pain all over my body and unrelenting fatigue, sleep disturbances, brain fog, etc. Diagnosed with Sjogren’s Syndrome and Fibromyalgia. Medication included Vicodin, Morphine and a muscle relaxer. I would not take Plaquenall (spelling?), Lyrica or other “biologics”. I was taking a bunch of supplements but nothing was improving.  

We have solid evidence showing that a ketogenic diet reduces seizures in children, sometimes as effectively as medication. Because of these neuroprotective effects, questions have been raised about the possible benefits for other brain disorders such as Parkinson’s, Alzheimer’s, multiple sclerosis, sleep disorders, autism, and even brain cancer. However, there are no human studies to support recommending ketosis to treat these conditions.
On the ketogenic diet, carbohydrates are restricted and so cannot provide for all the metabolic needs of the body. Instead, fatty acids are used as the major source of fuel. These are used through fatty-acid oxidation in the cell's mitochondria (the energy-producing parts of the cell). Humans can convert some amino acids into glucose by a process called gluconeogenesis, but cannot do this by using fatty acids.[57] Since amino acids are needed to make proteins, which are essential for growth and repair of body tissues, these cannot be used only to produce glucose. This could pose a problem for the brain, since it is normally fuelled solely by glucose, and most fatty acids do not cross the blood–brain barrier. However, the liver can use long-chain fatty acids to synthesise the three ketone bodies β-hydroxybutyrate, acetoacetate and acetone. These ketone bodies enter the brain and partially substitute for blood glucose as a source of energy.[56]
Over 8–10 mmol/l: It’s normally impossible to get to this level just by eating a keto diet. It means that something is wrong. The most common cause by far is type 1 diabetes, with severe lack of insulin. Symptoms include feeling very sick with nausea, vomiting, abdominal pain and confusion. The possible end result, ketoacidosis, may be fatal and requires immediate medical care. Learn more