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 >

By cutting carb intake significantly, we can drastically reduce insulin resistance, the precursor to type 2 diabetes. In addition, low carb diets, along with exercise, can be very effective at helping alleviate the symptoms and progression of type 2 diabetes. Beyond that, ketosis itself is appetite-suppressing, meaning your hunger will naturally check itself, increasing your caloric deficit and making you lose fat even faster. Read more about ketosis: What Is Ketosis, and How Long Does It Take to Get into Ketosis?
After increasing water intake and replacing electrolytes, it should relieve most all symptoms of Keto Flu. For an average person that is starting a ketogenic diet, eating 20-30g of net carbs a day, the entire adaptation process will take about 4-5 days. My advice is to cut your carbs to fewer than 15g to ensure that you are well on your way into ketosis within one week. If you are experiencing any more keto flu symptoms, double check your electrolyte intake and adjust.
If you’re new or just still learning the ropes for the keto diet food list, your biggest questions probably revolve around figuring out just what high-fat low-carb foods you can eat on such a low-carb, ketogenic diet. Overall, remember that the bulk of calories on the keto diet are from foods that are high in natural fats along with a moderate amount of foods with protein. Those that are severely restricted are all foods that provide lots of carbs, even kinds that are normally thought of as “healthy,” like whole grains, for example.
Following a ketogenic diet puts your body into a state of “ketosis,” which is a metabolic state that occurs when most of the body’s energy comes from ketone bodies in the blood, rather than from glucose from carbohydrate foods (like grains, all sources of sugar or fruit, for example). This is in contrast to a glycolytic state, where blood glucose (sugar) provides most of the body’s fuel (or energy).
Ketosis takes some time to get into – about two weeks of low carb eating is required for the initial adaptation. During this time there will be bouts of sluggishness, fatigue, headaches, and some gastrointestinal issues as you adapt, often referred to as “keto flu“. Proper electrolyte intake will correct most of these issues. In addition, the “diet” aspect of this ketogenic diet plan – that is, the caloric restriction – shouldn’t be worried about. Weight loss will come as your body regulates appetite as it the addiction to sugar and processed food lessens, so restricting calories during the initial two weeks isn’t recommended.

You’re very welcome, Judy! I’m glad it’s helpful. If you are keto (as opposed to low carb), unfortunately peaches would not allow you to stay in ketosis. You can check my keto food list to help determine what is keto friendly. Of course, there are worse things than fresh fruit 🙂 but in the end our bodies still see the sugar. That being said, it doesn’t mean you sabotaged the whole day. Just pick up again – you got this!! (And for next time, try some fresh berries in moderation when you’re craving fruit.)


Over the past century, ketogenic diets have also been used as natural remedies to treat and even help reverse neurological disorders and cognitive impairments, including epilepsy, Alzheimer’s symptoms, manic depression and anxiety. Research shows that cutting off glucose levels with a very low-carb diet makes your body produce ketones for fuel. This change can help to reverse neurological disorders and cognitive impairment, including inducing seizure control. The brain is able to use this alternative source of energy instead of the cellular energy pathways that aren’t functioning normally in patients with brain disorders.

Net carbs is simply total carbs minus fiber and non-digestible sugar alcohols, like erythritol. (This doesn’t apply to high glycemic sugar alcohols, like maltitol.) We don’t have to count fiber and certain sugar alcohols in net carbs, because they either don’t get broken down by our bodies, are not absorbed, or are absorbed but not metabolized. (Read more about sugar alcohols here.) 

Sulforaphane is a compound that is created when we crush or chew cruciferous vegetables. Once it is digested, sulforaphane activates a cytoprotective (cell-protecting) pathway that protects the cells from oxidative stress and removes toxins from the body. This is one of the main reasons why cruciferous vegetable consumption is linked to improved cognitive function and decreased cancer and heart disease risk.
What is the link between ketones and diabetes? Ketone is a chemical produced by the body when fats are broken down for energy. Ketone testing is important for people with diabetes, because high levels can lead to diabetic ketoacidosis (DKA), when acid levels become too high in the blood and the person loses consciousness. Find out when and why to do ketone testing. Read now
You’ll quickly find that salads are your friend when in ketosis, and for a good reason: they provide lots of food to fill you up, but they’re not going to bog you down. A bed of spinach with some red onion, bacon, a little tomato, and a hot sauce vinaigrette is quick and delicious. Add in some protein – perhaps that leftover salmon from day 1 – and you’ve got a complete, healthy lunch.
You’re very welcome, Judy! I’m glad it’s helpful. If you are keto (as opposed to low carb), unfortunately peaches would not allow you to stay in ketosis. You can check my keto food list to help determine what is keto friendly. Of course, there are worse things than fresh fruit 🙂 but in the end our bodies still see the sugar. That being said, it doesn’t mean you sabotaged the whole day. Just pick up again – you got this!! (And for next time, try some fresh berries in moderation when you’re craving fruit.)
The way that being on the keto diet makes you lose weight is by keeping insulin levels low. Insulin is a fat storage hormone that is released to help shuttle energy from the food you eat into your cells. This diet is known to be one of the best ways, besides fasting of course, to drop your insulin levels and low insulin is what is usually associated with fat loss. However, there is a misconception out there that your insulin will only go up with carbs. Protein can also spike your insulin levels and if you eat enough fats in one sitting, especially the wrong type of fats like trans fats, then that can spike your insulin levels as well.
Children who discontinue the diet after achieving seizure freedom have about a 20% risk of seizures returning. The length of time until recurrence is highly variable, but averages two years. This risk of recurrence compares with 10% for resective surgery (where part of the brain is removed) and 30–50% for anticonvulsant therapy. Of those who have a recurrence, just over half can regain freedom from seizures either with anticonvulsants or by returning to the ketogenic diet. Recurrence is more likely if, despite seizure freedom, an electroencephalogram shows epileptiform spikes, which indicate epileptic activity in the brain but are below the level that will cause a seizure. Recurrence is also likely if an MRI scan shows focal abnormalities (for example, as in children with tuberous sclerosis). Such children may remain on the diet longer than average, and children with tuberous sclerosis who achieve seizure freedom could remain on the ketogenic diet indefinitely.[46]
Aude, Y., A. S, Agatston, F. Lopez-Jimenez, et al. “The National Cholesterol Education Program Diet vs a Diet Lower in Carbohydrates and Higher in Protein and Monounsaturated Fat: A Randomized Trial.” JAMA Internal Medicine 164, no. 19 (2004): 2141–46. doi: 10.1001/archinte.164.19.2141. jamanetwork.com/journals/jamainternalmedicine/article-abstract/217514.

A ketogenic diet helps control blood sugar levels. It is excellent for managing type 2 diabetes, sometimes even leading to complete reversal of the disease. This has been proven in studies. It makes perfect sense since keto lowers blood-sugar levels, reduces the need of medications and reduces the potentially negative impact of high insulin levels.
Eggs are highly regarded as one of the perfect breakfast foods on the ketogenic diet. They are versatile and can be incorporated into many different dishes in many different forms. Beyond being low-carb and high-fat, eggs have powerful nutritional value. Eating eggs can increase your levels of high-density lipoprotein (or HDL) cholesterol, which is known to many as the "good" kind, which can result in a lowered risk of heart disease and stroke. We recommend that you scramble over to the egg aisle right away.
Thank you for such a wonderful informative article. You give everyone all this knowledge for free & people still want more. Give me printable versions of food list & protein charts. Come on people do a little leg work yourself, show some initiative. If you can’t your not going to be disciplined enough to make this diet work. There are links above to get free meal plans & more keto info. I’ve lost 60 lbs in 10 months & changed my life. My single best piece of advise? Buy a good keto info & recipe book. Key word in last sentence is “GOOD”. Hard copy for instant reference. Worth its weight in gold.
You’re very welcome, Judy! I’m glad it’s helpful. If you are keto (as opposed to low carb), unfortunately peaches would not allow you to stay in ketosis. You can check my keto food list to help determine what is keto friendly. Of course, there are worse things than fresh fruit 🙂 but in the end our bodies still see the sugar. That being said, it doesn’t mean you sabotaged the whole day. Just pick up again – you got this!! (And for next time, try some fresh berries in moderation when you’re craving fruit.)
Anticonvulsants suppress epileptic seizures, but they neither cure nor prevent the development of seizure susceptibility. The development of epilepsy (epileptogenesis) is a process that is poorly understood. A few anticonvulsants (valproate, levetiracetam and benzodiazepines) have shown antiepileptogenic properties in animal models of epileptogenesis. However, no anticonvulsant has ever achieved this in a clinical trial in humans. The ketogenic diet has been found to have antiepileptogenic properties in rats.[56]
Hi Linda, The carb counts on product packaging is accurate (they have to be, to abide by U.S. laws), though they are sometimes rounded down to the nearest gram. If your goal is weight loss, for some people these products can cause a stall, but others tolerate them fine. I personally avoid packaged products as they tend to be highly processed and contain artificial ingredients, but have not looked at this one specifically. We are gluten-free so don’t buy products with wheat, but I am a strong believer in each person doing what works best for them!
Anticonvulsants suppress epileptic seizures, but they neither cure nor prevent the development of seizure susceptibility. The development of epilepsy (epileptogenesis) is a process that is poorly understood. A few anticonvulsants (valproate, levetiracetam and benzodiazepines) have shown antiepileptogenic properties in animal models of epileptogenesis. However, no anticonvulsant has ever achieved this in a clinical trial in humans. The ketogenic diet has been found to have antiepileptogenic properties in rats.[56]
I have PCOS as well. Research a PCOS-specific diet. It often overlaps with Keto or Paleo recipes. But you have to also avoid holstein cow produced dairy products, red meat, pork, soy products (which are in almost every processed food) in addition to carbs and sugar. And absolutely avoid anything you can’t be sure doesn’t have extra hormones injected into it (like many mass-farmed meats). Vigorous exercise is also necessary to lose weight when you have PCOS (It’s much, much more difficult for us to lose weight than people with normal hormonal balances).
About 20% of children on the ketogenic diet achieve freedom from seizures, and many are able to reduce the use of anticonvulsant drugs or eliminate them altogether.[18] Commonly, at around two years on the diet, or after six months of being seizure-free, the diet may be gradually discontinued over two or three months. This is done by lowering the ketogenic ratio until urinary ketosis is no longer detected, and then lifting all calorie restrictions.[46] This timing and method of discontinuation mimics that of anticonvulsant drug therapy in children, where the child has become seizure-free. When the diet is required to treat certain metabolic diseases, the duration will be longer. The total diet duration is up to the treating ketogenic diet team and parents; durations up to 12 years have been studied and found beneficial.[9]
One downside to a ketogenic diet for weight loss is the difficulty maintaining it. “Studies show that weight loss results from being on a low-carb diet for more than 12 months tend to be the same as being on a normal, healthy diet,” says Mattinson. While you may be eating more satiating fats (like peanut butter, regular butter, or avocado), you’re also way more limited in what’s allowed on the diet, which can make everyday situations, like eating dinner with family or going out with friends, far more difficult. Because people often find it tough to sustain, it’s easy to rely on it as a short-term diet rather than a long-term lifestyle.
The first signs of ketosis are known as the “keto flu” where headaches, brain fogginess, fatigue, and the like can really rile your body up. Make sure that you’re drinking plenty of waterand eating plenty of salt. The ketogenic diet is a natural diuretic and you’ll be peeing more than normal. Take into account that you’re peeing out electrolytes, and you can guess that you’ll be having a thumping headache in no time. Keeping your salt intake and water intake high enough is very important, allowing your body to re-hydrate and re-supply your electrolytes. Doing this will help with the headaches, if not get rid of them completely.

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?
Gary D. Foster, Ph.D., Holly R. Wyatt, M.D., James O. Hill, Ph.D., Brian G. McGuckin, Ed.M., Carrie Brill, B.S., B. Selma Mohammed, M.D., Ph.D., Philippe O. Szapary, M.D., Daniel J. Rader, M.D., Joel S. Edman, D.Sc., and Samuel Klein, M.D., “A Randomized Trial of a Low-Carbohydrate Diet for Obesity — NEJM,” N Engl J Med 2003; 348:2082- 2090. http://www.nejm.org/doi/full/10.1056/NEJMoa022207.
Hi 😀 yes I have a question, just starting this Keto diet, so we’re very new at this but my boyfriend had a heart attack 8 years ago so we need to be very careful to not get to high on fat with him. Can he still benefit from this diet. His Doctor said he needs to get some of his weight off he is having a hard time breathing. The Doctor said a low carb diet. But I, we would like to try the Keto diet.
Aude, Y., A. S, Agatston, F. Lopez-Jimenez, et al. “The National Cholesterol Education Program Diet vs a Diet Lower in Carbohydrates and Higher in Protein and Monounsaturated Fat: A Randomized Trial.” JAMA Internal Medicine 164, no. 19 (2004): 2141–46. doi: 10.1001/archinte.164.19.2141. jamanetwork.com/journals/jamainternalmedicine/article-abstract/217514.
Certain studies suggest that keto diets may “starve” cancer cells. A highly processed, pro-inflammatory, low-nutrient foods can feed cancer cells causing them to proliferate. What’s the connection between high-sugar consumption and cancer? The regular cells found in our bodies are able to use fat for energy, but it’s believed that cancer cells cannot metabolically shift to use fat rather than glucose. (11)

Although many hypotheses have been put forward to explain how the ketogenic diet works, it remains a mystery. Disproven hypotheses include systemic acidosis (high levels of acid in the blood), electrolyte changes and hypoglycaemia (low blood glucose).[19] Although many biochemical changes are known to occur in the brain of a patient on the ketogenic diet, it is not known which of these has an anticonvulsant effect. The lack of understanding in this area is similar to the situation with many anticonvulsant drugs.[56]


Hi Gigi, Low carb and keto is about the balance of macronutrients eaten (fat, protein and carbs), not specifically meat or lack thereof. Most people on keto do eat meat, though some people do vegetarian keto. Fat is actually necessary for many body processes. There is no issue for the kidneys with a high fat diet, but if you eat too much protein that isn’t great for the kidneys. It’s a common misconception that keto is high protein (it isn’t). Keto is great for diabetics as it naturally helps stabilize insulin. All of this being said, please know I’m not a doctor and you should consult your doctor on any medical questions or before starting any diet. If you have more questions that aren’t medical questions, I recommend our low carb & keto support group here.
The easiest macro to calculate in the ketogenic diet is fat. Once you've got your carbs and protein set, simply fill the rest of your daily calorie needs with fat sources. If you find yourself wanting to gain a bit of weight, add approximately 500 calories, or 55 grams. If you want to lose weight, cut down on your fat intake by 200-500 calories, or 22-55 grams.

Keep an eye on your intake for nut or seed based foods, as they can be quite high in inflammatory omega 6’s. These include items like almonds, walnuts, pine nuts, sunflower oil and corn oil. Eating fatty fish and animal meat, keeping snacking to a minimum, and not over-indulging in dessert items that are dense in almond flour is usually enough to keep your omega’s at normal ranges.
First reported in 2003, the idea of using a form of the Atkins diet to treat epilepsy came about after parents and patients discovered that the induction phase of the Atkins diet controlled seizures. The ketogenic diet team at Johns Hopkins Hospital modified the Atkins diet by removing the aim of achieving weight loss, extending the induction phase indefinitely, and specifically encouraging fat consumption. Compared with the ketogenic diet, the modified Atkins diet (MAD) places no limit on calories or protein, and the lower overall ketogenic ratio (about 1:1) does not need to be consistently maintained by all meals of the day. The MAD does not begin with a fast or with a stay in hospital and requires less dietitian support than the ketogenic diet. Carbohydrates are initially limited to 10 g per day in children or 20 g per day in adults, and are increased to 20–30 g per day after a month or so, depending on the effect on seizure control or tolerance of the restrictions. Like the ketogenic diet, the MAD requires vitamin and mineral supplements and children are carefully and periodically monitored at outpatient clinics.[48]
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