Contact Us

Keto Breath: Why It’s a Problem and How to Fix It

Published December 10, 2018 (Revised: November 01, 2019) Read Time: 5 minutes
Ben Kissam

Written By: Ben Kissam, BS

Ben has a B.S. in Movement and Sports Science and over 7 years Certified Personal Training Experience.

Fact-Checked By: Ana Reisdorf MS, RD

keto-breath
<script type="application/ld+json"> { "@context":"http://schema.org", "@type":"BlogPosting", "author": { "@type": "Person", "name": "Ben Kissam, BS" }, "publisher": { "@type": "Organization", "name": "Warrior Made", "logo": { "@type": "ImageObject", "url": "https://www.warriormade.com", "image": "https://d1ghrtdbdq2gkr.cloudfront.net/media/public/2019/11/keto-breath-thumbnail-0029.jpg" } }, "headline":"Keto Breath: Why It’s a Problem and How to Fix It", "datePublished":"2018-12-10", "dateModified": "2019-11-01", "description":"You probably didn't expect bad breath to be a side-effect of your new low-carb diet. But it's called keto breath, and it's normal. Here's how to fix it.", "image": "https://d1ghrtdbdq2gkr.cloudfront.net/media/public/2019/11/keto-breath-thumbnail-0029.jpg" } </script> <script type="application/ld+json"> { "@context": "https://schema.org", "@type": "FAQPage", "mainEntity": [{ "@type": "Question", "name": "What is keto breath?", "acceptedAnswer": { "@type": "Answer", "text": "Keto breath is a common side effect you may experience when switching to a low-carb diet. Early on, you may notice smelly breath or a metallic taste in your mouth. Don’t worry, this is common.<br />Keto breath is primarily caused by your body’s increase in acetone, a ketone body*. The body produces acetone when it doesn’t have enough sugar.<br />(*Ketones, or ketone bodies, are compounds produced when the body enters ketosis. Research shows it takes up to 21 days to get into ketosis, but you can expedite the process by increasing physical activity, taking exogenous ketones—a popular keto supplement—and restricting carbs.<br />Keto breath is actually a sign that your body is in ketosis, burning fat as its primary fuel source.<br />Certain home ketone meter kits test the amount of acetone on your breath to determine if you’re in ketosis. Doctors like breath testing because it’s less invasive than taking blood or urine samples, but still accurate." } }, { "@type": "Question", "name": "Does keto breath go away?", "acceptedAnswer": { "@type": "Answer", "text": "Yes. The smell of ketones on your breath is a reflection of the elevated ketone levels in your blood.<br /> If you’re new to a low-carb or ketogenic diet, keto breath may persist for several weeks or up to a month. But as your body adapts to burning ketones for energy, that acetone buildup should diminish." } }, { "@type": "Question", "name": "Is ketosis breath a problem?", "acceptedAnswer": { "@type": "Answer", "text": "Obviously, having bad breath is not ideal. Because it’s easily treatable though, keto breath is more like an undesirable short-term side effect than a problem." } }, { "@type": "Question", "name": "How do you get rid of ketosis breath?", "acceptedAnswer": { "@type": "Answer", "text": "Here are some things you can do at home to mitigate or eliminate bad breath caused by a ketogenic diet: Eat more carbs, Eat less protein, Drink water, Practice good oral hygiene (or freshen your breath)." } }] } </script> <article> <div> <ul> <li><a href="#section1">What is Keto Breath?</a></li> <li><a href="#section2">Does Keto Breath Go Away?</a></li> <li><a href="#section3">Is Ketosis Breath A Problem?</a></li> <li><a href="#section4">How Do You Get Rid Of Ketosis Breath? (4 Tips)</a></li> <li><a href="#section5">Keto Breath: Wrapping Up</a></li> </ul> </div> <section> <p>There are many health benefits to a ketogenic diet. It can help reduce body weight, improve blood markers like good and bad cholesterol, and reduce your risk of many diseases <sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2716748/" rel="nofollow noreferrer">1</a></sup> <sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5452247/" rel="nofollow noreferrer">2</a></sup>.</p> <p>Any time you switch your diet though, there can be some unintended side effects. In the case of low-carb diets like keto, a common one is ‘keto breath’ or a foul odor that can linger for the first few weeks.</p> <p>Perhaps you’re wondering: <i>What causes keto breath? Is it a problem? And if you’re dealing with it, how can you fix it?</i></p> <p>Here’s everything you need to know, and 4 home remedies for eliminating keto breath.</p> </section> <hr class="divider-50 divider-medium mx-auto"> <section id="section1"> <h2>What is keto breath?</h2> <p><i>Keto breath</i> is a common side effect you may experience when switching to a low-carb diet. Early on, you may notice smelly breath or a metallic taste in your mouth. Don’t worry, this is common.</p> <p>Keto breath is primarily caused by your body’s increase in <i>acetone</i>, a ketone body*. The body produces acetone when it doesn’t have enough sugar <sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/pubmed/10634967" rel="nofollow noreferrer">3</a></sup>. </p> <p><i>(*<a target="_blank" href="https://www.warriormade.com/content/diet/ketosis-and-brain-function" rel="noreferrer">Ketones</a>, or ketone bodies, are compounds produced when the body enters ketosis <sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/pubmed/28599043" rel="nofollow noreferrer">4</a></sup>. Research shows it takes up to 21 days to <a target="_blank" href="https://www.warriormade.com/content/diet/how-long-does-it-take-to-get-into-ketosis" rel="noreferrer">get into ketosis</a>, but you can expedite the process by increasing physical activity, taking <a target="_blank" href="https://www.warriormade.com/content/diet/the-truth-about-exogenous-ketones-an-inside-look" rel="noreferrer">exogenous ketones</a>—a popular keto supplement—and restricting carbs <sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5506682/#Sec1title" rel="nofollow noreferrer">5</a></sup>.)</i></p> <p>Keto breath is actually a sign that your body is in <a target="_blank" href="https://www.warriormade.com/content/diet/fat-adapted-vs-ketosis-whats-the-difference" rel="noreferrer">ketosis</a>, burning fat as its primary fuel source<sup><a target="_blank" href="https://academic.oup.com/ajcn/article/76/1/65/4689461" rel="nofollow noreferrer">6</a></sup>.</p> <p>Certain <a target="_blank" href="https://www.warriormade.com/content/diet/how-to-measure-ketosis-with-a-home-ketone-meter/" rel="noreferrer">home ketone meter kits</a> test the amount of acetone on your breath to determine if you’re in ketosis. Doctors like breath testing because it’s less invasive than taking blood or urine samples, but still accurate <sup><a target="_blank" href="https://www.hindawi.com/journals/bmri/2014/869186/" rel="nofollow noreferrer">7</a></sup>.</p> <h3>What does ketosis breath smell like?</h3> <p>The smell of ketosis breath can be strange and sometimes unpleasant. </p> <p>The smell of your breath may remind you of nail polish; that’s because nail polish <i>is</i> acetone. </p> <p>But that’s not always the case. For some people, the smell can be sweet, even fruity<sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/books/NBK493179/" rel="nofollow noreferrer">8</a></sup>.</p> </section> <hr class="divider-50 divider-medium mx-auto"> <section id="section2"> <h2>Does keto breath go away?</h2> <p>Yes. The smell of ketones on your breath is a reflection of the elevated ketone levels in your blood <sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4471925/" rel="nofollow noreferrer">9</a></sup>. </p> <p>If you’re new to a low-carb or ketogenic diet, keto breath may persist for several weeks or up to a month. But as your body adapts to burning ketones for energy, that acetone buildup should diminish.</p> <p>In the meantime, there are some options to get rid of ketosis breath (see section: “How do you get rid of ketosis breath?” below).</p> </section> <hr class="divider-50 divider-medium mx-auto"> <section id="section3"> <h2>Is ketosis breath a problem?</h2> <p>Obviously, having bad breath is not ideal. Because it’s easily treatable though, keto breath is more like an undesirable short-term side effect than a problem.</p> <p>Other common symptoms of a low-carb diet include:</p> <ul> <li>Headaches</li> <li>Muscle cramps</li> <li><a target="_blank" href="https://www.warriormade.com/content/diet/keto-energy-how-the-keto-diet-combats-fatigue/" rel="noreferrer">Loss of energy</a></li> </ul> <p><i>***An important note: a ‘fruity’ smell on the breath is also a sign of ketoacidosis, a potentially life-threatening complication of type 2 diabetes where the body starts rapidly breaking down muscle <sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/books/NBK534848/" rel="nofollow noreferrer">10</a></sup>. Ketosis and ketoacidosis are not the same thing. </i></p> <p>As always, talk to your doctor before starting any new diet.</p> </section> <hr class="divider-50 divider-medium mx-auto"> <section id="section4"> <h2>How do you get rid of ketosis breath? (4 tips)</h2> <p>Here are some things you can do at home to mitigate or eliminate bad breath caused by a ketogenic diet.</p> <picture class="lazy-load"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/keto-breath-carbs-0029.webp" type="image/webp"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/keto-breath-carbs-0029.jp2" type="image/jpf"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/keto-breath-carbs-0029.jpg"> <img src="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/keto-breath-carbs-LR-0029.jpg" class="img-fluid" alt="keto-breath-carbs"> </picture> <h3>1. Eat more carbs</h3> <p>The bad breath smell you’re experiencing is the result of acetone, which your body produces when you’re depleted of carbs. If you’re purposely avoiding carbs to induce ketosis—and now have keto breath—consider upping your intake for a few days or weeks until you adapt.</p> <p>Remember, the keto diet is a low-carb diet, but it’s not a <i>no-carb</i> diet. You can eat 50 grams of carbs per day and stay in ketosis <sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/books/NBK499830/" rel="nofollow noreferrer">11</a></sup>. Add 5 or 10 more grams of carbs than normal and see if it helps. </p> <p>Just don’t overdo it. Stick to healthy, <a target="_blank" href="https://www.warriormade.com/content/diet/keto-fiber-foods-5-fiber-rich-foods-to-add" rel="noreferrer">high-fiber carbs</a>, so your blood sugar doesn’t elevate quickly.</p> <h3>2. Eat less protein</h3> <p>What we eat affects our metabolism and gut bacteria, both of which have an impact on our breath <sup><a target="_blank" href="https://www.cambridge.org/core/journals/journal-of-nutritional-science/article/effects-of-dietary-nutrients-on-volatile-breath-metabolites/961EAE61BD7458C0AB759C741B62F5A2" rel="nofollow noreferrer">12</a></sup>.</p> <p>Protein, for example, produces ammonia when it breaks down. Like acetone, ammonia can cause your breath to have a foul odor <sup><a target="_blank" href="https://www.nature.com/articles/s41598-018-20503-0" rel="nofollow noreferrer">13</a></sup>. </p> <p>Understand that eating protein isn’t <i>causing</i> keto breath. But it might help reduce the magnitude of the foul odor.</p> <picture class="lazy-load"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/keto-and-hydration-0029.webp" type="image/webp"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/keto-and-hydration-0029.jp2" type="image/jpf"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/keto-and-hydration-0029.jpg"> <img src="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/keto-and-hydration-LR-0029.jpg" class="img-fluid" alt="keto-and-hydration"> </picture> <h3>3. Drink water</h3> <p>Your body gets rid of ketones through urine, so staying hydrated can help reduce the amount of acetone that’s making your breath smell <sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/books/NBK247/" rel="nofollow noreferrer">14</a></sup>.</p> <p>The research surrounding the optimal amount of water you should drink varies. As a guideline, aim to drink water <i>before</i> you get thirsty. Thirst, along with a dry mouth and fatigue, are signs that you’re dehydrated <sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6282244/" rel="nofollow noreferrer">15</a></sup>.</p> <p>Staying hydrated can also help mitigate other early-onset keto symptoms like headaches or stomach problems <sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/books/NBK499830/" rel="nofollow noreferrer">16</a></sup>.</p> <picture class="lazy-load"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/oral-hygiene-keto-0029.webp" type="image/webp"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/oral-hygiene-keto-0029.jp2" type="image/jpf"> <source data-srcset="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/oral-hygiene-keto-0029.jpg"> <img src="https://d1ghrtdbdq2gkr.cloudfront.net/blog-content/oral-hygiene-keto-LR-0029.jpg" class="img-fluid" alt="oral-hygiene-keto"> </picture> <h3>4. Practice good oral hygiene (or freshen your breath)</h3> <p>Brushing your teeth regularly helps prevent plaque buildup, remove any food stuck in your teeth, and reduces the amount of bacteria on your tongue, all of which can cause bad breath <sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1570844/" rel="nofollow noreferrer">17</a></sup> <sup><a target="_blank" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3633265/" rel="nofollow noreferrer">18</a></sup>.</p> <p>Similar to tip #2, bad breath and keto breath aren’t one and the same. But a clean mouth can’t hurt if your breath smells bad.</p> <p>As you adjust to the diet, try brushing your teeth more frequently throughout the day.</p> <p>Other keto-friendly options to freshen your breath include: </p> <ul> <li>Drinking <a target="_blank" href="https://www.warriormade.com/content/diet/the-benefits-and-how-to-of-coconut-oil-coffee" rel="noreferrer">coffee</a> or tea (spicy tea with cinnamon in it is good for masking breath).</li> <li>Chewing sugar-free gum.</li> <li>Cooking with (or chewing on) fresh herbs like parsley or basil.</li> <li>Carrying mints or breath fresheners (again, go with sugar-free options).</li> </ul> </section> <hr class="divider-50 divider-medium mx-auto"> <section id="section5"> <h2>Keto breath: wrapping up</h2> <p>Here are a few quick hitters about keto breath: </p> <ul> <li>It’s a common side effect of a low-carb diet. It happens because acetone—a byproduct of restricting carbs—builds up, causing your breath to smell (usually sweet or acidic).</li> <li>It’s not a “problem,” per se. No one wants bad breath, though, so you may have to make some adjustments to get rid of it when you go low-carb.</li> <li>Eating more carbs, reducing protein, drinking more water, and keeping your breath fresh can help reduce keto breath (or bad breath in general). Your symptoms should subside after a few weeks.</li> </ul> <p>Admittedly, bad breath is not ideal for anyone. But the fat-burning abilities and other health benefits of keto far outweigh this minor inconvenience. Use these home remedies when you make the switch and it may not be a problem.</p> </section> </article>

Previous Post

Back to Diet

Next Post