Low-carb and keto
side effects
& how to cure them

Are you struggling while starting out on a low-carb or keto diet? Do you get headaches, leg cramps, constipation or any of the other more common side effects? Use the information on this page to avoid them – and feel great while losing weight.

The main solution to the most common problems when starting low carb might be to increase the intake of water and salt to replace what your body is losing.1 It’s even better to do it preventatively during the first week. If you do, you may not experience any of these problems, or they’ll likely only be minor and transient.2 Note: If you have high blood pressure, heart failure, or kidney disease, be sure to speak with your doctor before increasing your sodium intake.

Use one of the shortcuts below for specific problems – or just continue reading for all of them.

Top 7 common problems when starting

Less common issues on low carb

 

 
 

Induction flu: Headaches, lethargy, nausea, confusion, brain fog, irritability

The most common side effect on low carb is what most people experience during the first week, often on day 2-4. The “induction flu”, so called as it can mimic flu-like symptoms.

Headaches can occur during this transition, as can feeling tired, lack of motivation, nausea and lethargy. It’s also possible to experience confusion or “brain fog.”3

The good news is that these symptoms often disappear spontaneously within a few days. The even-better news is that these symptoms can perhaps be avoided altogether by consuming adequate water, salt, and fat on day one.4 The main cause is usually dehydration and/or salt deficiency, caused by a temporarily increased urine production.

The cure: water & salt

Salt & waterAny problems can potentially be prevented or at least minimized, by getting enough water and salt into your system to replace what is lost shortly after beginning a keto or low-carb diet.5

For example try adding half a teaspoon of salt to a large glass of water. Drink it. This may reduce or eliminate side effects within 15-30 minutes. If so, this may be repeated once daily if needed during the first week.

A better-tasting option is to use broth or bouillon, e.g. chicken, beef or bone broth, or vegetable broth.

The bonus: more fat

Make sure to eat enough fat.6 When going low carb, eating low fat is a recipe for starvation and feeling hungry and tired. You should never endure hunger as you start on a low-carb diet. A proper low-carb diet contains enough fat to make you feel satiated and energetic. This can help speed up the transition time and minimize the time spent feeling low when starting low carb.

So how do you get enough fat on low carb? There are any number of options, but when in doubt add butter to whatever you’re eating.

If necessary

If adding salt and water (and fat) does not completely eliminate the induction flu, the best option is usually to just hang in there. Any remaining symptoms are likely to be resolved within days, as your body adapts to low carb and begins using fat as its main fuel.

If necessary, it’s of course possible to have some carbs and make the transition to low carb more gradual and slower. This is not recommended as a first option, as it slows down the process and can make the weight loss and health improvement less obvious immediately.7

Learn more

Interview – Eric Westman Part 3
Do you want to know even more about how to get the maximum benefit and minimal side effects on low carb? Watch our five-part video course with Dr. Eric Westman on the membership site (free trial one month).

Avoiding transition problems like the induction flu is covered in part 3/5

 

 

Leg cramps

Leg cramps on a low-carb dietLeg cramps are not uncommon when starting a strict low-carb diet. It’s usually a minor issue if it occurs, but it can sometimes be painful. It may possibly be a side effect of the loss of minerals, specifically magnesium, due to increased urination. Here’s how to avoid it:

  1. Drink plenty of fluid and get enough salt. This may potentially reduce loss of magnesium and help prevent leg cramps.8
  2. If needed, supplement with magnesium. Here’s a suggested dosage from the book The Art and Science of Low Carbohydrate Living by Drs. Jeff Volek and Stephen Phinney: Take 3 slow-release magnesium tablets like Slow-Mag9 or Mag 64 a day for 20 days, then continue taking 1 tablet a day afterwards.10
  3. If the steps above are not enough and the problem is bothersome, consider increasing your carb intake somewhat. This may eliminate the problem. The more carbs you eat though, the weaker the impact of the low-carb diet.

Alternatively, for even more information and tips, check out our full guide:

Leg pain in a girl on bed,

Six ways to kick nasty leg cramps to the curb

Guide Here are the six key things to know to kick your leg cramps to the curb, in our full leg cramps guide.

 

 

Constipation

Constipation is another possible side effect, especially during the first time on a low-carb diet, as your digestive system may need time to adapt.11

Constipation on a low-carb dietHere are the three steps to cure it; perhaps you only need the first one:

  1. Drink plenty of fluid and get enough salt. One common cause of constipation on low carb may be dehydration. This makes the body absorb more water from the colon and thus the contents get dryer, harder and constipation can result. The solution is to drink plenty of water and perhaps add some extra salt.
  2. Eat plenty of vegetables or another source of fiber. Getting enough good-quality fiber from the diet keeps the intestines movin, which may reduce the risk of constipation. This can be more of a challenge on low carb where many sources of fiber are avoided, but eating plenty of non-starchy vegetables may solve this problem. Another, and completely carb-free, option for adding fiber to the diet is psyllium seed husks (can be dissolved in water) or ground flaxseed.1213
  3. If the steps above are not enough, take 2 to 4 tablespoons (30-60 ml) Milk of Magnesia (magnesium hydroxide) to relieve constipation.14 Amazon link

 


Bad breath

Bad breath on low carbOn a strict low-carb diet some people experience a characteristic smell from their breath, a fruity smell that often reminds people of nail polish remover.

The smell is from acetone, a ketone body. This is a sign that your body is burning lots of fat and even converting lots of fat to ketones to fuel the brain.15

This smell can sometimes also turn up as body odor, especially if working out and sweating a lot.

Not everyone eating a ketogenic low-carb diet experiences this ketone breath – and for most people who do, it’s a temporary thing that often goes away after a week or two.16

For some people it does not go away, though, and it can be a problem. Here are the possible solutions. The first two are more general, the next three more targeted to the keto smell specifically.

  1. Drink enough fluid and get enough salt. If your mouth feels dry – and it often can when just starting a strict low-carb diet and getting into ketosis – this means you have less saliva to wash away bacteria. This can result in bad breath, so make sure to drink enough.
  2. Maintain a good oral hygiene. Brushing your teeth twice a day won’t stop the fruity keto smell (that comes from your lungs), but at least it won’t be mixing with other smells.
  3. Use a breath freshener regularly. This can mask the keto smell.
  4. Wait another week or two and hope for it to be temporary.
  5. Reduce the degree of ketosis. If the smell is a long-term problem and you want to get rid of it, the easy way is to reduce the degree of ketosis. This means eating a bit more carbs; 50-70 grams per day may be enough to get out of ketosis.17 Of course, this will likely reduce the effect of the low-carb diet when it comes to weight loss and diabetes, etc., but for some people it may still be powerful enough. Another option is to eat 50-70 grams of carbs per day and add some intermittent fasting. This may get you roughly the same effect as a strict low-carb diet… without the smell.18


 
 

Heart palpitations

Heart palpitations on a low-carb dietIt’s common to experience a slightly elevated heart rate during the first few weeks on low carb. It’s also common to experience that the heart is beating a bit harder. This is normal and usually nothing to worry about.

One common cause may be dehydration and a lack of salt. A reduction in the amount of circulating fluid in the bloodstream means that the heart will have to pump blood slightly harder or faster to maintain blood pressure.

The cure

The quick solution to this problem is to drink enough fluids and make sure to get enough salt.

If necessary

If adding salt and water does not completely eliminate heart palpitations, it might also be a result of stress hormones released to maintain blood sugar levels19 (if you’re on diabetes medication see the section below). This is often a temporary problem as the body adapts to a lower-carb diet and may go away within a week or two.

In the uncommon situation that the problem persists – and the palpitations are bothersome to you – try to slightly increase the carb intake. This will reduce the effect of the low-carb diet somewhat, so it’s a trade-off.

It’s possible that supplementing with magnesium may decrease palpitations.20 Taking up to 400 mg of magnesium per day (the recommended dietary allowance, or RDA) is safe for people with normal kidney function.

Important note if on medication for diabetes or high blood pressure

Medical Alert

Diabetes

Avoiding the carbohydrates that raise your blood sugar decreases your need for medication to lower it. Taking the same dose of insulin as you did prior to adopting a low-carb diet might result in a low blood sugar. One of the main symptoms of this is heart palpitations.

You need to monitor your blood sugar frequently when starting this diet and adapt (lower) your medication. This should ideally be done with the assistance of a knowledgeable physician. If you’re healthy or a diabetic treated either by diet alone or just with Metformin there is no risk of hypoglycemia.

Learn more about diabetes medications and low carb

High blood pressure

On a low-carb diet an elevated blood pressure tends to improve (normalize).21 This can reduce the need for medication and your dosage may become too strong, leading to low blood pressure. One of the symptoms of this can be an increased pulse and heart palpitations. If you experience this it’s wise to check your blood pressure (here’s a good home monitor). If it’s low – e.g. under 110/70 – you should contact your doctor to discuss possibly reducing or discontinuing your blood pressure medication.

Learn more about blood pressure and low carb

 
 

 

Reduced physical performance

Reduced physical performance on low carbIn the first few weeks on a low-carb diet your physical performance can be severely reduced. There are two main reasons for this:

  1. Lack of fluid and salts. This cause of most early problems when starting low carb can really hinder physical performance. Drinking a large glass of water with 0.5 teaspoons of salt or a glass of broth 30–60 minutes before exercising might make a huge difference in performance.
  2. Adaptation to burning fat takes weeks. The second cause of reduced early performance is not as quickly fixed. It simply takes time for your body to shift from being a sugar-burner to burning primarily fat for energy, even in the muscles.22 It takes weeks or a few months. This adaptation might be faster the more you exercise while on a low carb, high fat diet.23 The end result can have many benefits (see below).

Increasing physical performance on low carb

While transitioning to a low-carb, high-fat (LCHF) diet often reduces physical performance initially, the long-term effect has many potential benefits.24 This is something that has only recently begun to be appreciated. In fact, a lot of elite athletes are now experimenting with LCHF diets.

The benefits of a LCHF diet in sports are mainly seen in long-distance running and other endurance events. The body’s fat stores are huge compared to its glycogen stores. This means that once fat-adapted, an athlete may be able to perform for long periods of time without needing much (if any) external energy. This frees the athlete from having to activate his or her gastrointestinal tract during activity – a large amount of blood flow can instead be directed to the muscles. This also minimizes the risk of digestive issues during the activity.

Another benefit comes from the reduction of body fat usually seen on low carb.25 This reduction in body-fat percentage and lightening of your body can be a huge bonus for most sports.

Watch Professor Stephen Phinney explain more about physical performance on low carb

Learn more

Do you want to learn much more about maximizing your physical performance on low carb? Then check out our interviews with several of the world’s leading experts on the topic, as well as the movie Run on Fat and people with their own experience to guide you:


 

Hair loss on low carb

Temporary hair loss

Temporary hair loss can occur for many different reasons, including any big dietary change. This is especially common when severely restricting calories (e.g. starvation diets, meal replacements).26 But it can also occasionally happen on low-carb diets.27

If so, it usually starts 3-6 months after starting a new diet, at which point you’ll notice an increasing amount of hairs falling out when brushing your hair.

The good news is that even if you should be so unfortunate, this is only a temporary phenomenon. And only a percentage of your hair will fall out (the thinning will rarely be very noticeable to others).

After a few months, all the hair follicles will start to grow new hair, and when you have regrown your hair it will be as thick as before again. Of course, if you have long hair this could take a year or even more.
 

Background

To understand exactly what is happening it’s necessary to know the basics of how hair grows.

Every single hair strand on your head usually grows for about 3-5 years at a time. After that it stops growing for up to 2 months. Then a new hair strand starts growing in the same hair follicle, pushing the old hair out.28

Thus, you’re losing hair every day, but as the hair strands are unsynchronized this is not so noticeable. You lose one hair and another starts growing, so you always have about the same number of hair strands on your scalp.

Stress and synchronized hair loss

If your body experiences significant stress, more hair strands than usual can enter the resting phase at the same time.29 This can happen for many reasons, like these:

  • Starvation, including calorie-restricted diets and meal replacements
  • Diseases
  • Unusually demanding exercise
  • Pregnancy
  • Breast feeding
  • Nutrient deficiencies
  • Psychological stress
  • Any big diet change

As the new hair strands start growing a few months later all these formerly resting hair strands will drop at almost the same time. This is called “telogen effluvium” in fancy medical terms (read more about it), and it’s relatively common.

What to do

If there was an obvious triggering factor 3-6 months before the problem started – such as giving birth or transitioning to a strict low-carb diet – you don’t really have to do anything. In all likelihood the problem will be temporary.

As long as you eat a varied and nutritious low-carb diet it’s very unlikely that stopping it will speed up the hair regain; it will likely happen as quickly anyway. And unfortunately, you can’t stop the hair loss from happening once it has started, as the resting hairs will fall out whatever you do.

It’s possible to order blood tests for nutrient deficiencies, but unless you are on a vegetarian or vegan diet (with no supplements of iron or vitamin B12) it’s unlikely that they will show anything interesting.30

How to minimize the risk of hair loss when starting low carb

First, temporary hair loss is relatively rare after starting a low-carb diet.31

There are no studies on how to minimize this small risk, but it’s likely helpful not to restrict calories, i.e. don’t do a low-carb and low-fat diet (which your body may perceive as starvation). Instead, eat as much fat as you need to feel satisfied and not hungry, an LCHF diet.32

It may also be helpful to reduce other sources of stress during your first few weeks on low carb. Sleep well, be kind to yourself in general, and preferably don’t start an intense exercise program at the same time (wait at least a couple of weeks).

 


 

Elevated cholesterol

High cholesterol on a low-carb dietFirst, the great news: A low-carb high-fat diet usually results in an improved lipid profile, suggesting a lower risk of heart disease:33

The classic effect of a low-carb diet on cholesterol is a slight elevation, partly due to an elevation of HDL cholesterol (often referred to as “good” cholesterol), indicating a potentially lower risk of heart disease. In addition, the cholesterol profile also typically improves in two more ways: lower triglycerides and larger, less dense LDL particles.34

It has also been shown that two years with low-carb, high-fat diet advice may result in reduced signs of atherosclerosis.35

Potentially troubling cholesterol results

However, there are also potential problems, even if they are rare. On average, the elevation of total and LDL cholesterol is so small that many studies do not even pick up on it. But for a minority of people – possibly around 5-15% of the population – there can be worrying elevations of LDL and total cholesterol, beyond what can be considered normal.36 This potential risk is worth taking seriously. It can also be worth taking steps to correct it.

For example, a small subgroup of people can end up with total cholesterol numbers over 400 mg/dl (10 mmol/l) on a strict low-carb diet, and LDL numbers over 250 mg/dl (6.5 mmol/l).37 This is not normal. Even if the lipid profile is otherwise good – with high HDL and low triglycerides – it may be unhealthy. While there are compelling theories that this could be physiologically appropriate and not dangerous, we do not have convincing data to prove safety.

Looking closer at modern cholesterol tests in such cases, there’s usually a high LDL particle count, and the apoB and apoB/A1 values are usually abnormally high. These numbers all indicate a potentially increased risk of heart disease.

What to do

If you get a concerning lipid profile on a low-carb diet there are a few things to consider, in this order:

  1. Stop drinking Bulletproof coffee (butter, coconut fat or MCT oil in coffee). Don’t drink significant amounts of saturated fat at all when you’re not hungry. This alone may normalize cholesterol levels.38
  2. Only eat when hungry and consider adding intermittent fasting which might reduce cholesterol levels in some cases.39
  3. Consider using more unsaturated fats, like olive oil, fatty fish and avocados. Whether it will improve your health is unknown, but it will probably lower your cholesterol.40 And as it’s abnormally high, that may be enough of a reason.
  4. If step 1-3 is not enough: Consider whether you really need to be on a strict keto diet for health reasons. If a more moderate or liberal diet (e.g. 50–100 grams of carbs per day) can still work for you, it may also likely lower your cholesterol. Just remember to choose good unprocessed, high-fiber carb sources like vegetables, nuts, and seeds rather than wheat flour or refined sugar.
  5. Consult with your doctor: You should discuss with your healthcare provider if medication therapy is warranted.

Learn more

For much more about low carb and cholesterol, see our full guide:

Cholesterol and low-carb diets

More details

LCHF and LDL – Dr. Sarah Hallberg
For more details about low carb and the percentage of people who get higher LDL cholesterol, watch this talk by Dr. Sarah Hallberg.

Regarding statins

When cholesterol is high and especially for people with preexisting heart disease, the question of cholesterol-lowering medication, statins, is often discussed. These drugs do lower the risk of heart disease, but at the risk of side effects, like reduced energy, muscle pain and an increased risk of diabetes type 2.

For people with preexisting heart disease, the relatively modest risk of side effects is often outweighed by the benefits. For people without heart disease, it’s often less clear. Discuss any change in medication with your doctor.

My cholesterol

FWIW, here are my cholesterol tests after 10 years on a low-carb, high-fat diet.

 


 

A low-carb diet and reduced alcohol tolerance

Low carb and alcohol tolerance

When on a strict low-carb diet people may need significantly less alcohol to get intoxicated.41 So be careful the first time you drink alcohol on low carb. Possibly, you’ll need half as many drinks as usual to enjoy yourself the most. Low carb may save you money at the bar.

The reason for this common experience is still unclear. It could be because the liver is busy producing ketones or glucose, and thus has less capacity to spare for burning alcohol, slowing down the process.

Alternatively, it could be because alcohol and sugar (fructose) are partly broken down in similar ways in the liver. Eating less sugar could thus make your liver temporarily less adapted to break down alcohol, just like drinking less alcohol would.

No matter the reason, you’ll likely tolerate less alcohol on low carb. Be prepared for it.

Obviously, if you’re going to be driving be extra careful. Don’t ever drink and drive, period.

For more, check out our two top low-carb and keto alcohol guides:

Low-carb alcohol – the best and the worst drinks
Alcohol and the keto diet: 7 things you need to know

 


 

Gout and low carb

Gout and low carb It’s often claimed that low-carb diets high in meat could cause gout by increasing uric acid levels. This is likely wrong for two reasons:

  1. A low-carb diet should not be high in meat, only moderate. 42
  2. The risk of gout likely goes down on low carb, at least long term.43

However, there may possibly be a slight increase in the risk of gout during the first few weeks on a strict low-carb diet.44

For more on what really causes gout and how to avoid it, check out our full guide:

Gout and low carb

 

More

  1. It’s been known for decades that when insulin levels drop —as they do when carb intake is very low—the kidneys excrete more sodium and water, although the exact mechanism isn’t clear:

    American Journal of Physiology. Renal Physiology 2007: Insulin’s impact on renal sodium transport and blood pressure in health, obesity, and diabetes [overview article; ungraded]

    Diabetalogia 1981: The effect of insulin on renal sodium metabolism [overview article; ungraded]

  2. This is based on consistent clinical experience of low-carb practitioners. [weak evidence]

  3. This is based on the consistent clinical experience of low-carb practitioners. [weak evidence]

  4. This is based mainly on the consistent clinical experience of doctors who prescribe low-carb diets for their patients. [weak evidence]

  5. This piece of advice is based on theory and consistent experience from clinicians using it, and people testing it. [weak evidence]

    There’s also some support from a study that found only minor increases in side effects in low-carb participants who were advised to drink bouillon:

    Nutrition & Metabolism 2008: The effect of a low-carbohydrate, ketogenic diet versus a low-glycemic index diet on glycemic control in type 2 diabetes mellitus [randomized trial; moderate evidence]

  6. A low-carb diet is high in natural fats, including saturated fat. Although the issue remains somewhat controversial, several recent systematic reviews of randomized controlled trials and large observational studies have failed to show a connection between eating saturated fat and increased heart disease risk:

    Open Heart 2016: Evidence from randomised controlled trials does not support current dietary fat guidelines: a systematic review and meta-analysis [strong evidence]

    Nutrition Journal 2017: The effect of replacing saturated fat with mostly n-6 polyunsaturated fat on coronary heart disease: a meta-analyses of randomised controlled trials [strong evidence]

  7. A systematic review of 14 trials found that eating very low carb appears to be more effective than more modest carb restriction for fat loss:

    Obesity Reviews 2016: Impact of low-carbohydrate diet on body composition: meta-analysis of randomized controlled studies [strong evidence]

  8. This is mainly based on the clinical experience of clinicians who prescribe low-carb diets for their patients. [weak evidence]

  9. Diet Doctor will not benefit from your purchases. We do not show ads, use any affiliate links, sell products or take money from industry. Instead we’re funded by the people, via our optional membership. Learn more

  10. This recommendation is based on the research of Drs. Volek and Phinney, who have conducted dozens of trials in people following very-low-carb diets. [weak evidence]

  11. In a study of people with type 2 diabetes who ate 20 or fewer grams of carbs per day, slightly more than half complained of constipation at some point during the trial:

    Nutrition & Metabolism 2008: The effect of a low-carbohydrate, ketogenic diet versus a low-glycemic index diet on glycemic control in type 2 diabetes mellitus [randomized trial; moderate evidence]

  12. Diet Doctor will not benefit from your purchases. We do not show ads, use any affiliate links, sell products or take money from industry. Instead we’re funded by the people, via our optional membership. Learn more

  13. Clinical Nutrition ESPEN 2019: Effect of flaxseed or psyllium vs. placebo on management of constipation, weight, glycemia, and lipids: a randomized trial in constipated patients with type 2 diabetes [moderate evidence]

  14. Taking a standard dose of magnesium hydroxide is considered safe for people with normal kidney function and can be expected to produce a bowel movement within several hours:

    Clinics in Colon and Rectal Surgery 2010: Medical management of constipation [overview article; ungraded]

  15. Breath ketone meters measure the amount of acetone in your breath in order to confirm that your body is burning fat and producing ketones:

    Obesity 2015: Measuring breath acetone for monitoring fat loss: review [overview article; ungraded]

    Ketones can be used to help fuel the brain when carbs are limited or even avoided altogether: Food for thought: does the brain need carbs?

  16. This is based on consistent clinical experience from low-carb practitioners. [weak evidence]

  17. Most studies on ketogenic diets limit carbs to less than 50 grams per day in order to promote nutritional ketosis:

    The British Journal of Nutrition 2013: Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials [strong evidence]

    Experienced clinicians have reported that patients are often unable to remain in ketosis when consistently eating more than 50 grams of carbs per day.[weak evidence]

  18. International Journal of Obesity 2011: The effects of intermittent or continuous energy restriction on weight loss and metabolic disease risk markers: a randomised trial in young overweight women [moderate evidence]

    Cureus 2018: Intermittent fasting: the choice for a healthier lifestyle [review of 4 randomized trials; moderate evidence]

  19. International Journal of Obesity and Related Metabolic Disorders 1983: Adrenaline: a physiological metabolic regulatory hormone in humans? [overview article; ungraded]

  20. In one study, increasing magnesium intake by 50% helped reduce symptoms in people with frequent heart palpitations:

    Journal of the American College of Cardiology 1997: Antiarrhythmic effects of increasing the daily intake of magnesium and potassium in patients with frequent ventricular arrhythmias [randomized trial; moderate evidence]

  21. This has been shown in several high-quality trials:

    Obesity Reviews 2012: Systematic review and meta-analysis of clinical trials of the effects of low carbohydrate diets on cardiovascular risk factors [strong evidence]

  22. Metabolism 1983: The human metabolic response to chronic ketosis without caloric restriction: physical and biochemical adaptation [non-controlled trial; weak evidence]

  23. This is based on several personal reports from people who have exercised during the keto-adaptation period.
    [very weak evidence]

  24. Sports 2019: Keto-adaptation and endurance exercise capacity, fatigue recovery, and exercise-induced muscle and organ damage prevention: a narrative review [overview article; ungraded]

  25. This has been shown in both obese people and athletes:

    Obesity Reviews 2016: Impact of low-carbohydrate diet on body composition: meta-analysis of randomized controlled studies [strong evidence]

    Sports 2018: The three-month effects of a ketogenic diet on body composition, blood parameters, and performance metrics in CrossFit trainees: a pilot study [non-randomized trial; weak evidence]

  26. Journal of the American Medical Association 1976: Alopecia in crash dieters [case series report; very weak evidence]

  27. This is based on the clinical experience of low-carb practitioners. [weak evidence]

  28. Indian Journal of Dermtalogy, Venerology and Leprology 2013: Telogen effluvium [overview article; ungraded]

  29. Journal of Clinical & Diagnostic Research 2015: Telogen effluvium: a review [overview article; ungraded]

  30. Low-carb diets that contain both animal and plant foods typically provide adequate amounts of all vitamins and minerals:

    BMJ Open 2018: Assessing the nutrient intake of a low-carbohydrate, high-fat (LCHF) diet: a hypothetical case study design [descriptive study; ungraded]

  31. This is based on the clinical experience of low-carb practitioners. [weak evidence]

  32. In many low-carb studies showing health benefits, people are advised to eat a moderate amount of protein and as much fat as needed to feel satisfied:

    Diabetes Therapy 2018: Effectiveness and safety of a novel care model for the management of type 2 diabetes at 1 year: an open-label, non-randomized, controlled study [weak evidence]

    Applied Physiology, Nutrition and Metabolism 2017: A 12-week low-carbohydrate, high-fat diet improves metabolic health outcomes over a control diet in a randomised controlled trial with overweight defence force personnel [moderate evidence]

  33. Nutrition Reviews 2019: Effects of carbohydrate-restricted diets on low-density lipoprotein cholesterol levels in overweight and obese adults: a systematic review and meta-analysis [strong evidence]

    British Journal of Nutrition 2016: Effects of low-carbohydrate diets v. low-fat diets on body weight and cardiovascular risk factors: a meta-analysis of randomised controlled trials [strong evidence]

    Cardiovascular Diabetology 2018: Cardiovascular disease risk factor responses to a type 2 diabetes care model including nutritional ketosis induced by sustained carbohydrate restriction at 1 year: an open label, non-randomized, controlled study [nonrandomized study; weak evidence]

  34. Some studies suggest that smaller LDL particles are more harmful because they may be more likely to become trapped in the arteries:

    Current Vascular Pharmacology 2014: Insulin resistance, small LDL particles, and risk for atherosclerotic disease [overview article; ungraded]

  35. Circulation 2010: Dietary intervention to reverse carotid atherosclerosis [randomized trial; moderate evidence]

  36. In studies, some people eating low-carb diets have experienced a 30-44% increase in LDL cholesterol:

    Atherosclerosis 2018: Effect of a low carbohydrate, high fat diet on LDL cholesterol and gene expression in normal-weight, young adults: a randomized controlled study [moderate evidence]

    Sports 2018: The three-month effects of a ketogenic diet on body composition, blood parameters, and performance metrics in CrossFit trainees: a pilot study [non-randomized trial; weak evidence]

  37. This is based on the clinical experience of low-carb practitioners. [weak evidence]

  38. Consuming a lot of saturated fat has been shown to increase the number of LDL particles in some people:

    PLoS One 2017: Effects of a very high saturated fat diet on LDL particles in adults with atherogenic dyslipidemia: a randomized controlled trial [moderate evidence]

  39. The American Journal of Clinical Nutrition: Short-term modified alternate-day fasting: a novel dietary strategy for weight loss and cardioprotection in obese adults [randomized trial; moderate evidence]

    Metabolism: Alternate day fasting (ADF) with a high-fat diet produces similar weight loss and cardio-protection as ADF with a low-fat diet [randomized trial; moderate evidence]

  40. A study in people with metabolic syndrome found that consuming fish oil and olive oil for 3 months significantly lowered their LDL cholesterol levels:

    Nutrition 2015: Effects of extra virgin olive oil and fish oil on lipid profile and oxidative stress in patients with metabolic syndrome [randomized trial; moderate evidence]

  41. This is commonly reported by people on a keto diet. However, there isn’t much scientific research yet to explain why tolerance seems to be reduced, just theories:

    Low carb and alcohol #6: Lower tolerance, worse hangovers

  42. Moderate protein is roughly 1.2-1.7 grams per kg of ideal body weight per day. Learn more: How much protein should you eat?

  43. In a randomized trial of people who ate a high-protein, low-carb diet for six months, uric acid levels declined, especially in those who were obese:

    American College of Rheumatology 2014: High-protein diet (Atkins diet) and uric acid response [randomized trial; moderate evidence]

    There’s also some interesting early research suggesting that a ketogenic diet may help reduce gout flares, although much more study is needed:

    Cell Reports 2017: β-hydroxybutyrate deactivates neutrophil NLRP3 inflammasome to relieve gout flares [rat study; very weak evidence]

  44. Most studies have found no differences in uric acid levels among people on low-carb diets vs. low-fat or control diets

    Diabetes Metabolism Research & Reviews 2018: Effect of low-carbohydrate diet on markers of renal function in patients with type 2 diabetes: a meta-analysis
    [systematic review of randomized trials; strong evidence]

    Yet some low-carb researchers and clinicians have reported that some people who start eating low-carb diets experience an initial temporary rise in uric acid levels that could potentially slightly increase gout risk. [weak evidence]