10 signs the keto diet is working for you

"When you are in ketosis, ketones are providing more oxygen and energy to your cells," registered dietitian Jennifer Masson told INSIDER. That, along with increased blood flow, will give you an increased sense of energy, improved mental clarity, and focus, she added.

"Stable blood sugar levels caused from ketosis help prevent the up and down roller coaster of hunger you would normally experience with a carb-filled diet," Masson said.

A study in The Journal of Physiology confirmed that ketones can lower blood sugar by testing patients using a ketone supplement. The researchers at the University of British Columbia and University of Oxford demonstrated that a single drink of ketone ester enables better control of blood sugar by reducing spikes in sugar levels. 

"When your body starts to produce ketones, you may not be adept at metabolizing them for fuel," Masson said. One way the body gets rid of them is through the breath, which can smell pretty bad, she suggested.

Once you become better at using the ketones as fuel, the bad breath will eventually subside, she added.

Masson also said that your kidneys pump out more fluid and electrolytes when your body is in ketosis. This may affect your bladder and cause you to urinate more often, she said.

"When you first go on the keto diet, you will lose a lot of water," Masson suggested. The storage form of sugar (glycogen) needs three molecules of water for every molecule of glycogen, she said, and when your body starts to use up the stored water, you will urinate more causing your total body weight to go down.

Eventually increased fat loss will also be a source of weight reduction, she added.

"Because of slight dehydration (potentially from increased urination) and electrolyte loss, you may feel a little sluggish, achy, and fatigued," said Masson.  These are a group of symptoms known as the keto flu, she suggested, and adding some electrolytes (especially sodium and water) to your diet will help decrease your chance of getting it.

Because of large amounts of fat being added to your diet, Masson said that gastrointestinal distress sometimes happens when you start the keto diet. You may also experience diarrhea and constipation because of the overall loss of electrolytes and dehydration, she said.

Because of biochemical changes happening in your body, Masson suggested that stress can actually cause your body to produce cortisol (a stress hormone which causes sleep disruption)  before your body starts producing and using ketones efficiently.

This may cause some sleepless nights when you first start the diet, she said.

"Because of increased water loss, (if you are not getting enough fluids) you may experience dry mouth," said Masson. To avoid this uncomfortable sensation, she recommended drinking beverages like water, unsweetened coffee, or tea throughout the day to stay hydrated.

"The best way to tell if you're in ketosis is to buy some ketone test strips," suggested nutrition coach Malorie Thompson. Knowing for sure what's going on, rather than playing a guessing game, is well worth the investment, she said. 

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