Why am I having heart palpitations on keto? What could possibly make my breath smell like an old sailor’s grandpa’s hat? Where is all this pee coming from, and perhaps more troubling, why am I pooping so little? These are all things I wish someone would have told me when I started keto, but alas they didn’t. Despite the great wealth of knowledge on what bone broth pairs best with MCT oil and coffee, there’s a lot of little ins-and-outs that people experience on a ketogenic diet that need explaining.
Whether you’re new to the diet, jumping back on the wagon, or a seasoned veteran, there’s something here for you. I also want to preface this post with the fact that I’m not a doctor. I’m a guy who lost a lot of weight doing a ketogenic diet plan. This list is based on my own anecdotal experience and the fact that I found many others who shared these experiences. I took our collective issues and did some research and came up with these 5 points as the most confounding.
1 – Heart palpitations
The first thing I would say about keto heart palpitations is to always consult your doctor. That said, I had 2 types of heart irregularities during my first and main bout of keto.
- PVCs, or premature ventricular contractions. These felt like skipped heart beats mostly, but they can feel like fluttering, too. My doctor told me that unless they’re happening a lot, they’re likely benign. Before I knew that, though, they scared me terribly.
- Heavy, pounding heartbeats. These were the worst, and it was almost always at night. I am predisposed to anxiety, for which I was being treated, but these pounding heartbeats made it so much worse. I would frequently lay in bed, terrified of my heart exploding. From what I’ve gathered, these extremely heavy heartbeats are common in first-time ketoers.
So what’s the solution here? Well, chances are good it’s an electrolyte deficiency, and in particular magnesium. While I got plenty of sodium from salty food and potassium from the avocados (read: guacamole) I was eating, I wasn’t doing great with magnesium. Supplementing magnesium is the easiest solution, and because there’s about a hundred different forms of magnesium for sale, let me say that you specifically want magnesium glycinate.
You can supplement potassium as well by using Lite Salt (there’s tons of different brands), and sodium is super easy. Keeping your electrolytes in check will keep your heart from going goofy.

2 – Difficulty sleeping
I’m going to piggyback on the previous entry and touch on difficulty with sleep. Besides the heavy heartbeats that made me restless and robbed me of sleep, I found sleep in general to be frustrating. You might experience:
- Restlessness
- Anxiety about sleeping or bedtime in general
- Jolting awake significantly more than normal (5-10 times or more)
- Waking up in the middle of the night and not being able to fall back to sleep
If you’re having difficulty sleeping on keto, then magnesium deficiency is probably to blame (again). It is, however, not the only potential culprit. Other things that lead to bad sleep that are exacerbated in ketosis are:
- Drinking caffeine too late in the day (after noon, typically) – caffeine is fat soluble, and without excessive carbs to blunt absorption, the effects at least seem more potent. It’s a good idea to knock off the coffee early in the day.
- Eating fat too close to bedtime – since your body in ketosis is much better at utilizing fat for fuel, you may experience an effect similar to a “sugar rush” when you consume fats. The burst of energy from a fat bomb might be nice during a workout, but it’s not a good midnight snack.
- Not exercising – once you’re fat adapted, you will have more energy in general, it’s just a fact. If you’re not utilizing that energy, however, it can make you restless. In addition, exercise helps clear neurotransmitter trash out of the brain, and makes you physically tired, two components of good rest. I’m not even going to list all the of the non-weightloss benefits of exercise, but just know that losing weight is the least useful impact of exercise. YOU SHOULD EXERCISE.
3 – Hot flashes
If you are experiencing menopause and trying to do keto, this part might seem like a “kicking-me-while-I’m-down” segment, but it’s a real thing unfortunately. As a 29 year old male, I kept having hot flashes, and I’d wake up drenched in sweat in the middle of the night. After ruling out various diseases that cause night sweating with my doctor, I searched for a link to my keto diet and sweating.
I found ample links between exercise and increased sweating – this is because the body begins to anticipate strenuous exercise, even if you’re just getting up off the couch. The fitter you are the more you might experience this, actually. What I found was:
- Exercising increases your body’s sweat response during even mundane physical exertion.
- Well-maintained ketosis increases thermogenesis, which though it burns fat, also increases core body temperature.
- There also appears to be an electrolyte link here, too – I found that during periods of heavy sweating, I could drink pickle juice and it leveled off.
So if you’re experiencing hot flashes on keto, know that it’s most likely some facet of your diet. It’s just a thing you get used to (more or less).
4 – Bathroom irregularities
Questions I see the most with keto newbies typically entail changes in bathroom habits. Typically they are something like:
- Peeing more on keto – quick answer here is that your body stores glycogen in water within your muscles and liver, and once your body utilizes all the stored glycogen, you don’t need that water. This means lots and lots of pee, particularly in the first week.
- Pooping far less on keto – there are a couple things at work here, but the combination of less waste (because you’re not eating as many garbage carbs) and typically less bulk in your foods tends to slow things down. Slowly increase your veggies, especially fibrous greens, and make sure you’re getting 100+ ounces of water a day (and add a bit of salt to your water).
- Stomach cramping – Increasing fat intake hurts your stomach sometimes because of how quickly it can digest. Anecdotally, coffee seems to have a harsher effect on the stomach in ketosis, causing general pain and cramping.
- Right-side cramping, followed by extreme urgency to poop – Typically related to gallstones, gallbladder spasms, or biliary colic. Keto seems to make gallbladder issues worse, and it has to do with rapid fat loss. As your body processes more fat, it steps up the bile production, and that can cause gallstones. Keep your water intake up, and see a doctor if you think you’re having gallbladder issues, as they can be excruciatingly painful and potentially life-threatening if untreated.
- Exacerbation of IBS symptoms (particularly cramping and diarrhea) – If your IBS is controlled with medication (dicyclomine for instance), then take your medication as needed. Any changes in diet will make IBS worse typically, as your gut adjusts. If your IBS isn’t controlled, talk to your doctor about getting some medication – it changed my life, and it’s super generic and cheap.
A lot of these will even out as you diversify your diet and get used to processing more fat.
5 – Smells
You might have heard about “keto breath”, a lovely side effect of your body breaking down ketones. One of the byproducts of ketones is acetone, which exits the body through our breath. You might know acetone for it’s starring roll in nail polish remover. Now imagine that smell in your mouth. In addition, keto causes:
- Increased, acrid body odor – as wonderful as that sentence sounds, it’s unfortunately quite common. There are a few reasons for this.
- Excess protein used for glucose production – your body is really efficient at burning fat for energy, and if you have a LOT of body fat, your liver can make excess glucose for your brain with mostly fat. If not, it will need to use protein to make glucose, and byproducts of that are ammonia (ammonia-like odor), methylamine (fishy odor), and hydrogen sulfide (rotten egg odor). The good news is that these smells are more common in leaner ketoers, since they have less adipose tissue to burn. To combat these, make sure your bathing game is on-point and drink a lot of water.
- Stinky pee – They (stores) sell ketone test strips. Originally intended for diabetics to make sure they’re not heading towards ketoacidosis, ketone test strips have experienced a surge in popularity for keto dieters. Well, they’re a waste of money and they’re stupid, because if you’re in ketosis, your pee will smell and be darker. There, I saved you $15.
- Onion/garlic stink – Whatever the primary cause of this smell, it’s going to come out in your mucus and sweat, so if you smell it, figuring out if it’s in your nose or on your skin might be difficult. Just know that it’s because you’re keto (or eating a lot of onions and garlic). Exercise and water seemed to help me, but your mileage may vary.
Is this all the weirdness?
Nope, there’s definitely more oddness to keto than just these 5, but these in particular vexed me when I first started. You can read a million articles that talk about “keto flu” or muscle cramps, but most don’t dig into this stuff, so I hope this information is helpful. At the very least, I hope it helps ease some mental anguish – the sweating and heartbeat problems terrified me until I finally figured it out.
What are some weird keto side effects you’ve experienced that I didn’t cover? I’d love to hear about them, as would anyone else who is dealing with them, I’m sure.