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 >

For anyone, regardless of any underlying health issues, the so-called keto flu is a possibility (and even likelihood) as your body adjusts to ketosis on the keto diet, says Tori Schmitt, RDN, founder of YES! Nutrition, LLC based in Dayton, Ohio. Fatigue, irritability, headaches, and nausea are all symptoms of the keto flu, Schmitt says. Fortunately, keto flu lasts only about one to two weeks.
“Certainly, the quality of fat counts,” says Yawitz. “There’s a big difference nutritionally between bacon and almonds. As much as possible, people set on the keto diet should emphasize plant-based, unsaturated fats like nuts, seeds, olive oil, and avocado, which have even been shown to protect the heart.” If you have high cholesterol or other risk factors for heart disease, you should speak with your doctor before beginning the keto diet. This is because the diet may — but doesn't have to — include large amounts of saturated fat. Some studies have shown increases in cholesterol and triglycerides in people following the diet, while other research reveals that the keto diet may actually decrease heart disease risk as well as saturated fat intake.

Fascinating stuff and I am quite curious how we know for certain one is actually in ketosis i.e. using ketones as primary fuel source BECAUSE we do know that glucose has a shorter metabolic pathway to burn and under most conditions, given the presence of glucose, that is what the body will default to which is why high fat and high sugar together in diet is so detrimental. So if we use one or more of the above “boosters” and show high levels of blood ketones but also highish levels of glucose (during initial transition) will be mostly burning ketones or still defaulting to glucose?


For someone more interested in health/muscle gain rather than weight loss, should I up the protein and good carb levels a bit? I’m around 10% BF and weigh 220, so I require a higher calorie intake the average. In just a few days striving for a Keto-diet, I’m averaging between 50-60g gross carbs (30g net), 160g protein and 220 fat (8%-22%-70%) DO you think that is a good target or should I try and adjust?

The Keto diet emphasizes weight loss through fat-burning. The goal is to quickly lose weight and ultimately feel fuller with fewer cravings, while boosting your mood, mental focus and energy. According to Keto proponents, by slashing the carbs you consume and instead filling up on fats, you safely enter a state of ketosis. That’s when the body breaks down both dietary and stored body fat into substances called ketones. Your fat-burning system now relies mainly on fat – instead of sugar – for energy. While similar in some ways to familiar low-carb diets, the Keto diet’s extreme carb restrictions – about 20 net carbs a day or less, depending on the version – and the deliberate shift into ketosis are what set this increasingly popular diet apart.
Some clinicians[37] regard eliminating carbohydrates as unhealthy and dangerous.[38] However, it is not necessary to eliminate carbohydrates from the diet completely to achieve ketosis. Other clinicians regard ketosis as a safe biochemical process that occurs during the fat-burning state.[35] Ketosis, which is accompanied by gluconeogenesis (the creation of glucose de novo from pyruvate), is the specific state that concerns some clinicians. However, it is unlikely for a normally functioning person to reach life-threatening levels of ketosis, defined as serum beta-hydroxybutyrate (B-OHB) levels above 15 millimolar (mM) compared to ketogenic diets among non diabetics, which "rarely run serum B-OHB levels above 3 mM."[39] This is avoided with proper basal secretion of pancreatic insulin. People who are unable to secrete basal insulin, such as type 1 diabetics and long-term type II diabetics, are liable to enter an unsafe level of ketosis, eventually resulting in a coma that requires emergency medical treatment.[citation needed] The anti-ketosis conclusions have been challenged by a number of doctors and advocates of low-carbohydrate diets, who dispute assertions that the body has a preference for glucose and that there are dangers associated with ketosis.[40][41]
I see a lot of people say that ketosis is great for insulin sensitivity. BUT, in my experience ketosis causes physiological insulin resistance whereby the muscles and liver are sparing glucose for the brain. Hence, glucose tolerance actually goes down during ketosis. As such, is it possible that post workout carbs could do a lot more damage than they would on a non-ketogenic diet? Or maybe, as Kiefer suggests, glucose uptake post workout is not moderated by insulin at all i.e. muscles soak up glucose regardless of their insulin sensitivity? Or maybe cyclical ketosis doesn’t allow liver glycogen to get low enough to trigger physiological insulin resistance?
^ Yiu H. Hui (February 1985). Principles and issues in nutrition. Wadsworth Health Sciences Division. p. 91. Retrieved 2014-05-19. Eskimos actually consume more carbohydrates than most nutritionists have assumed. Because Eskimos frequently eat their meat raw and frozen, they take in more glycogen than a person purchasing meat with a lower glycogen content in a grocery store. The Eskimo practice of preserving a whole seal or bird carcass under an intact whole skin with a thick layer of blubber also permits some proteins to ferment into carbohydrates.
In ketogenesis, two acetyl-CoA molecules instead condense to form acetoacetyl-CoA via thiolase. Acetoacetyl-CoA momentarily combines with another acetyl-CoA via HMG-CoA synthase to form hydroxy-β-methylglutaryl-CoA. Hydroxy-β-methylglutaryl-CoA form the ketone body acetoacetate via HMG-CoA lyase. Acetoacetate can then reversibly convert to another ketone body—D-β-hydroxybutyrate—via D-β-hydroxybutyrate dehydrogenase. Alternatively, acetoacetate can spontaneously degrade to a third ketone body (acetone) and carbon dioxide, although the process generates much greater concentrations of acetoacetate and D-β-hydroxybutyrate. When blood glucose levels are low, ketone bodies can be exported from the liver to supply crucial energy to the brain.[28]
Why is the keto diet good for you? A keto diet is one that prioritizes fats and proteins over carbohydrates. It can help reduce body weight, acne, and the risk of cancer. Find out about the mechanisms through which it achieves these benefits and the research that supports it. This MNT Knowledge Center article also discusses the risks of the diet. Read now

^ Bechtel PJ (2 December 2012). Muscle as Food. Elsevier Science. pp. 171–. ISBN 978-0-323-13953-3. Retrieved 19 May 2014. Freezing does stop the postmortem metabolism but only at about −18ºC and lower temperatures. Above −18ºC increasing temperatures of storage cause an increasing rate of ATP breakdown and glycolysis that is higher in the comminuted meat than in the intact tissue (Fisher et al., 1980b). If the ATP concentration in the frozen tissue falls below ~ 1 µmol/g no contraction or rigor can occur because they are prevented by the rigid matrix of ice.
A study in the Journal of Applied Physiology showed that people who do twice-a-day workouts, but defy standard nutrition recommendations by not eating for two hours after the first session (thus depleting carbohydrate stores with the first session) experienced a better ability to burn fat (with no loss in performance) compared with a group that trained only once a day and ate carbohydrates afterward.

Remember how important it is to measure ketone blood levels accurately? Same goes for food tracking. A food tracking app, like MyFitnessPal, provides insight into macronutrient intake and thus the ability to tweak the diet to achieve ketosis. Tracking diet (inputs) and measuring ketones levels (outputs) delivers the best shot at optimizing the keto diet plan.
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This answer made me sad. Having lived in New York all of my life, I from a young age saw loved ones fall victim to spontaneous gluten intolerance and restaurants run to their rescue with accommodating menus.  This is why I get annoyed. What’s a dietary prescription for someone who wants to go to a dinner party and be able to eat a meal that was prepared for them? Keto is cultish not for its members’ radical commitment to a dietary restriction but for their lack of full participation in the outside world.
Wow! Amazing article. I don’t read blogs regularly, but I’ll be reading more of yours. I am on day 11 of a fast to get me into ketosis; 7 days bone broth and now on day-4 water only. Intentions are weight loss (10# down, 15# more to go) and immunity improvement/gut help. Planning 9 days of whey water, fermented veggies and mad probiotics when the water days are done (day 14?). After this fast I want to stay fat adapted, start training again and get down to 8% body fat. I believe you have cut that journey significantly with this article. Thank you.
“Adequate dietary carbohydrate is critical to raise muscle glycogen to high levels in preparation for the next day’s endurance competition or hard training session. Accordingly, during the 24 h prior to a hard training session or endurance competition, athletes should consume 7-12 g of carbohydrate per kilogram of body weight. However, during the 24 h prior to a moderate or easy day of training, athletes need to consume only 5-7 g of carbohydrate per kilogram of body weight.”
Weight loss benefits ushered the keto diet into the spotlight. That’s how most people have likely heard about ketones, a fuel source created naturally by the body when burning fat. But more and more research points to diverse applications of ketones in the blood outside of just fat loss, from improved endurance performance to the treatment of medical conditions like epilepsy.
“Loss of muscle mass as we age has a number of serious consequences,” notes Clark. “Muscle is metabolically active and helps boost daily energy expenditure and mitigate age-related weight gain.” Losing muscle mass can also decrease functional strength and heighten the risk of falls, notes Clark. Falls are the top cause of death from injury in older populations, according to the Institute of Medicine Division of Health Promotion and Disease Prevention.
Checking your ketone level is one way to know if you’re in ketosis. This metabolic state usually kicks in after three or four days of restricting your carbohydrate intake or going through periods of intermittent fasting. You don’t have to visit a doctor to measure your level. Pick up a ketone urine test from a nearby drug store, or use a blood sugar meter that’s capable of measuring ketones.
The ketogenic diet is usually initiated in combination with the patient's existing anticonvulsant regimen, though patients may be weaned off anticonvulsants if the diet is successful. Some evidence of synergistic benefits is seen when the diet is combined with the vagus nerve stimulator or with the drug zonisamide, and that the diet may be less successful in children receiving phenobarbital.[18]
The Johns Hopkins Hospital protocol for initiating the ketogenic diet has been widely adopted.[43] It involves a consultation with the patient and their caregivers and, later, a short hospital admission.[19] Because of the risk of complications during ketogenic diet initiation, most centres begin the diet under close medical supervision in the hospital.[9]
Hi Maya. I LOVE your site!! Interesting, informative with fab recipes and ideas. Hubby and I have just started eating low carb and I have to say, we are not finding it too difficult and I already feel sooo much better!! I find the hardest part is choosing low carb veg, I feel as if we are not eating enough. Any suggestions on how to get more veggies into our diet?

A: The amount of weight you lose is entirely dependent on you. Obviously adding exercise to your regimen will speed up your weight loss. Cutting out things that are common “stall” causes is also a good thing. Artificial sweeteners, dairy, wheat products and by-products (wheat gluten, wheat flours, and anything with an identifiable wheat product in it).
Following the ketogenic diet and achieving ketosis may be beneficial if you’re living with type 2 diabetes and need to manage your symptoms. Limiting carbohydrate intake is crucial with type 2 diabetes because too many carbs can increase blood glucose levels, which can damage blood vessels and lead to vision problems, kidney problems, and nerve problems.
Awesome info. I’ve been LCHF moderate protein (about 1 g per lean lbs/mass) and 50-100g of carbs for about a year. I’d consume around 2500 cals. I’m active 4-5 days a week (60-90 min cycling sessions) I started using MCT/Butter coffee. It surpressd my appetite and I would only eat whole food at lunch/dinner…still LCHF, but since my appetite was lower I was only takin in about 1800 cals. After about 2 weeks I started to gain body fat. Do you think the reduced caloric intake is the culprit? Should I “force” myself to eat…maybe up the MCT intake to make up the difference?
C12 is about 50+% of coconut oil, and it requires a pit stop in the liver rather than getting immediately converted into energy like the other MCT’s listed above. This is why it is more accurately described as an LCT, not an MCT like marketers claim. It raises cholesterol more than any other fatty acid. It is also commonly cited as having antimicrobial benefits, which is does – except the shorter chain MCT oils are more effective against candida yeast infections, and even gonorrhea and chlamydia.
The keto diet is often called a fad diet. Make no mistake: it is. But unlike other trendy diets, the keto diet is unique because it actually pushes the body into an alternate, natural metabolic state called ketosis. When this happens, you can reliably expect a few negative side effects, notably those that come with the "keto flu." But other side effects emerge only when people implement the keto diet poorly, typically by failing to eat balanced, nutrient-rich foods as a part of a high-fat, low-carb diet.
Hi Stacey, I can’t give medical advice and definitely recommend following your doctor’s recommendations. You can ask him/her if low carb would be better suited for you. Also, you may want to double check with him/her if the kidney concern was related to high protein, because that is a common misconception about keto – it is not a high protein diet/lifestyle.
Adherence to a keto diet food list isn’t always great, though. A review published in January 2015 in the Journal of Clinical Neurology found that only 45 percent of participants were able to follow the approach as prescribed. “The poor compliance was attributed to side effects, social isolation, and cravings,” says Yawitz. And some people in the study “reported the diet simply wasn’t helping them lose weight,” she adds. Brissette agrees with this line of thinking. “In my opinion, the keto diet isn't sustainable and takes the joy and fun out of eating,” she says.
Fairly recently, the diet was introduced as a weight-loss diet by an Italian professor of surgery, Dr. Gianfranco Cappello of Sapienza University in Rome. In his 2012 study, about 19,000 dieters received a high-fat liquid diet via a feeding tube inserted down the nose. The study showed an average weight loss of more than 20 pounds in participants, most of whom kept it off for at least a year. The researchers reported a few minor side effects, like fatigue.
There are many misconceptions about ketosis. The most common is mixing it up with ketoacidosis – a rare and dangerous medical condition that mostly happen to people with type 1 diabetes if they don’t take insulin. Even some health care professionals tend to mix up these two situations somewhat, perhaps due to the similar names and a lack of knowledge about the distinct differences.
Your glycogen stores can still be refilled while on a ketogenic diet. A keto diet is an excellent way to build muscle, but protein intake is crucial here. It’s suggested that if you are looking to gain mass, you should be taking in about 1.0 – 1.2g protein per lean pound of body mass. Putting muscle on may be slower on a ketogenic diet, but that’s because your total body fat is not increasing as much.5Note that in the beginning of a ketogenic diet, both endurance athletes and obese individuals see a physical performance for the first week of transition.
Longer-term ketosis may result from fasting or staying on a low-carbohydrate diet (ketogenic diet), and deliberately induced ketosis serves as a medical intervention for various conditions, such as intractable epilepsy, and the various types of diabetes.[6] In glycolysis, higher levels of insulin promote storage of body fat and block release of fat from adipose tissues, while in ketosis, fat reserves are readily released and consumed.[5][7] For this reason, ketosis is sometimes referred to as the body's "fat burning" mode.[8]
But while carbohydrates can help you have a better workout, go faster, or go longer, this only applies to acute, in-the-moment performance. Once you take a look (which you’re about to do) at the long-term effects of chronic high blood sugar levels, things change drastically. If the damage that you’re above to discover is worth it to you, then you are either mildly masochistic or you value performance much more than health.
The longer cholesterol circulates in your bloodstream, the higher the likelihood that it will dig its way into an endothelial wall and potentially contribute to atherosclerosis or plaque formation. This is why it’s so dangerous to eat a high-fat diet, but to also have your nightly dark chocolate bar, overdo it on the red wine, or have weekly “cheat days” with pizza, pasta, or sugar-laden ice cream.
During the 1920s and 1930s, when the only anticonvulsant drugs were the sedative bromides (discovered 1857) and phenobarbital (1912), the ketogenic diet was widely used and studied. This changed in 1938 when H. Houston Merritt, Jr. and Tracy Putnam discovered phenytoin (Dilantin), and the focus of research shifted to discovering new drugs. With the introduction of sodium valproate in the 1970s, drugs were available to neurologists that were effective across a broad range of epileptic syndromes and seizure types. The use of the ketogenic diet, by this time restricted to difficult cases such as Lennox–Gastaut syndrome, declined further.[10]

^ Jump up to: a b c Clemente FJ, Cardona A, Inchley CE, Peter BM, Jacobs G, Pagani L, Lawson DJ, Antão T, Vicente M, Mitt M, DeGiorgio M, Faltyskova Z, Xue Y, Ayub Q, Szpak M, Mägi R, Eriksson A, Manica A, Raghavan M, Rasmussen M, Rasmussen S, Willerslev E, Vidal-Puig A, Tyler-Smith C, Villems R, Nielsen R, Metspalu M, Malyarchuk B, Derenko M, Kivisild T (October 2014). "A Selective Sweep on a Deleterious Mutation in CPT1A in Arctic Populations". American Journal of Human Genetics. 95 (5): 584–589. doi:10.1016/j.ajhg.2014.09.016. PMC 4225582. PMID 25449608.
When you eat foods high in carbohydrates and fat, your body naturally produces glucose. Carbohydrates are the easiest thing for the body to process, and therefore it will use them first – resulting in the excess fats to be stored immediately. In turn, this causes weight gain and health problems that are associated with high fat, high carbohydrate diets (NOT keto).
In addition to the seaweed and glycogen carbohydrates mentioned above, the Inuit can access many plant sources. The stomach contents of caribou contain a large quantity of partially digested lichens and plants, which the Inuit once considered a delicacy. They also harvested reindeer moss and other lichens directly. The extended daylight of the arctic summer led to a profusion of plant life, and they harvested plant parts including berries, roots and stems, as well as mushrooms. They preserved some gathered plant life to eat during winter, often by dipping it in seal fat.[71]
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
^ Jump up to: a b Cardona A, Pagani L, Antao T, Lawson DJ, Eichstaedt CA, Yngvadottir B, Shwe MT, Wee J, Romero IG, Raj S, Metspalu M, Villems R, Willerslev E, Tyler-Smith C, Malyarchuk BA, Derenko MV, Kivisild T (2014). "Genome-wide analysis of cold adaptation in indigenous Siberian populations". PLOS One. 9 (5): e98076. Bibcode:2014PLoSO...998076C. doi:10.1371/journal.pone.0098076. PMC 4029955. PMID 24847810.

Strawberries are another delicious, sweet, and filling fruit that you can eat in moderation on the keto diet. A ½-cup serving of sliced strawberries contains about 4.7 g of net carbs and 4.1 g of sugar. As there are only 27 calories in the aforementioned serving, you can eat strawberries raw, add a few pieces to your cereal, or blend a handful into a small low-carb smoothie. Strawberries also have antioxidant and anti-inflammatory benefits, per a study published in February 2010 in the Journal of Medicinal Food. The same ½ cup provides 48.8 mg of vitamin C (81.3 percent DV), 127 mg of potassium (2.7 percent DV), and 20 micrograms of folate (5 percent DV).


This is the second shortest form of MCT, also rare and comprising about 8% of coconut oil. It is slower to turn into energy but less expensive than C8. XCT Oil is triple-distilled in a non-oxygen atmosphere with no solvents, and it contains C10 and C8, because these are the only two MCT oils that turn into ATP quickly without the liver. You would need 6 tablespoons of coconut oil to get one tablespoon of XCT oil.
In addition, most studies that compare carbohydrate utilization with fat utilization fail to take into account the fact that full “fat adaptation” that allows you to gain all the benefits of using fat as a fuel actually takes time – often more than four weeks – and up to a couple years. But since most studies that compare fat and carbohydrate burning are short-term, you rarely see the benefits of this kind of fat adaptation actually fleshed out in research. Instead, the average research participant begins the study in a non-fat adapted state, gets either a high fat or high carb diet, then launches into exercise. But in an ideal study, that person would have followed either a high-fat or high-carb diet for many months before getting their fat burning capability investigated.
After that happened, I set out once again to find some kind of carbohydrate source that allows one to maintain elevated liver glycogen and muscle glycogen stores without getting all the blood-sugar level roller coaster rides or gut rot and fermentation that many typical sports nutrition carbohydrate sources such as fructose and maltodextrin can cause.
I asked James Fell if he had some practical advice on sustainable dieting. “When it comes to weight loss,” he said, “the only thing that matters is caloric deficit. However, quality of diet affects quantity. A higher quality diet is more likely to be one that allows you to eat a lower quantity of calories and still be satisfied. That being said, there are many different ways to find a high-quality diet.”
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