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The Keto Flu: Symptoms & Remedies

A keto diet, also known as low carb high fat (LCHF), low carb diet, or ketogenic diet, is well known for being a low carb diet, where the body produces ketones in the liver to be used as energy. 

Burning fat seems like an ideal way to lose pounds, however, getting the liver to make ketone bodies requires that you deprive yourself of carbs, fewer than 50g of carbs per day (keep in mind that a medium-sized apple has about 25g of carbs) and around 1.5 g of protein per kilogram of body weight.

Also, eating too much protein can interfere with ketosis. It usually takes a few days to reach a state of ketosis.

What Is Keto Flu?

Keto flu is a group of side effects that hit most people when they first switch from a higher carb diet to a ketogenic one.

It happens as a result of the body adjusting to running on a different ratio of macronutrients (fewer carbs, more fat, and protein).

Keto Flu Symptoms

When you transition into ketosis shortly after starting the keto diet, you might experience keto flu symptoms like:

  • heart palpitations;
  • stomach pain;
  • sugar cravings;
  • trouble falling or staying asleep;
  • lack of concentration or focus;
  • muscle cramping or soreness;
  • diarrhea or constipation;
  • irritability;
  • nausea;
  • dizziness or confusion;
  • brain fog.

Note – most people feel one or more of these symptoms during the first week of a ketogenic diet, particularly days 3-5.

The severity and duration of the keto flu symptoms vary a lot between people. For instance, some people feel terrible for a day and others for a couple of weeks, while others hardly notice anything.

It depends on your health status, nutrition, and lifestyle before starting the ketogenic diet.

How Long Does The Keto Flu Last?

These symptoms usually last from several days to 14 days, and up to a month at most.

According to Kristen Mancinelli, RD, author of The Ketogenic Diet:

“It takes a while, usually a week or two, for the metabolic machinery to shift to fat-burning mode. And you’ll feel pretty crummy while the transition is happening.”

Remedies & Tips

During this transition phase, there are several methods to reduce, manage, or prevent symptoms of the keto flu.

#1 Electrolytes

Electrolytes are minerals which are involved in many essential processes in your body, such as:

  • helping build new tissue;
  • helping the blood to clot;
  • transmitting nerve signals from muscle and nerve cells to other cells;
  • enabling muscle contractions, including the beating of the heart;
  • keeping the pH of the blood in the normal range (7.35-7.45, slightly alkaline);
  • regulating the fluid levels in the blood plasma and the body.

Replenishing your electrolytes is a great way to start feeling better fast since the ketogenic diet acts as a natural diuretic, thus, to counteract that you have to make sure you are giving your physical body extra sodium (salt).  Take note of the key players – potassium, magnesium, and sodium.

Foods high in electrolytes are:

  • spinach, almonds, cashew nuts, flaxseeds, or Brazill nuts for magnesium; this mineral helps with keto flu symptoms like dizziness, muscle cramps, and fatigue;
  • Himalayan salt or Celtic sea salt to provide chloride and sodium;
  • winter squash, avocado, Swiss chard, or broccoli for potassium; this mineral helps with keto flu symptoms if you are battling constipation, cramps, or muscle weakness.

#2 Start Slowly

Start with a typical low-carb diet, for the first couple of days. Get your body used to a low carb diet before you restrict them to the extent that you do during the ketogenic diet.

#3 Avoid Strenuous Exercise

Activities like intense running, biking, strenuous workouts, and weight lifting may have to be put on the back burner while your system adapts to new fuel sources. Therefore, strenuous exercise should be avoided when experiencing keto flu symptoms.

While these types of exercise should be avoided if you are experiencing the keto flu symptoms, light activities such as yoga, walking, or leisurely biking may improve symptoms.

#4 Stay Hydrated

Dehydration will make just about every keto flu worse. Drinking enough water is particularly important if you experience symptoms like diarrhea or vomiting because they cause you to lose fluids.

In addition to drinking water, you can also eat hydrating foods such as green juices.

Important note – if your urine is dark yellow, this means you need to drink more water.

But how much water should you drink?

According to the Institute of Medicine of the National Academies, your total water goal (including all beverages and food) should be around 3.7 liters for men and 2.7 liters for women a day.

Factors that influence water needs are:

  • overall health – your body loses fluids when you have vomiting, fever, or diarrhea. Other conditions which might require increased fluid intake include urinary tract stones and bladder infections.
  • environment – humid or hot weather can make you sweat. Dehydration can also occur at high altitudes.
  • exercise – if you do any activity which makes you sweat, you need to drink extra water. It is recommended to drink water before, during, and after a workout.

#5 Avoid These Foods

During keto flu, it is recommended to avoid the following foods:

  • sweet alcoholic and non-alcoholic beverages;
  • artificial sweeteners;
  • processed foods;
  • maple syrup;
  • honey;
  • high fructose corn syrup;
  • cane sugar and raw sugar;
  • starchy vegetables including carrots and sweet potatoes;
  • most fruits, especially tropical ones like oranges, pineapples, bananas, papayas, and mangoes; grapes and apples too;
  • beans such as kidney, pinto, lima, black, and chickpeas;
  • grains like wheat, barley, rye, buckwheat, oats, rice, quinoa, and sprouted grains.

#6 Foods To Eat

During keto flu, it is best to eat the following foods:

  • pumpkin seeds;
  • watercress;
  • hemp seeds;
  • lettuce;
  • Swiss chard;
  • spinach;
  • mustard greens;
  • kale;
  • collard greens;
  • walnuts;
  • pecans;
  • asparagus;
  • macadamia nuts;
  • avocados;
  • Brazil nuts;
  • bok choy;
  • celery;
  • almonds;
  • eggplant;
  • kohlrabi;
  • turnips;
  • radishes;
  • rapini (broccoli raab);
  • zucchini;
  • okra;
  • artichokes;
  • Brussels sprouts;
  • broccoli;
  • cabbage;
  • fennel;
  • cucumbers;
  • cauliflower;
  • flax seeds;
  • chia seeds. 

#7 Get Adequate Sleep

Lack of sleep causes levels of cortisol (the stress hormone) to rise in the body, which can negatively impact mood and make keto-flu symptoms worse.

Image credit – Shutterstock

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