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Hormonal issues become more common as you age, and while men do experience the effects of hormonal changes, women tend to be affected to a greater degree. A ketogenic diet has a somewhat unique impact on hormones, as well as the thyroid, menstruation cycles, and the HPA axis. In this article, we will cover this impact, as well as the effect keto has on hormones like cortisol. Using this information, you can make the appropriate adjustments to your diet and lifestyle – to truly improve your health.

What Is the Keto Diet?

keto diet hormones

The keto diet — also referred to as the ketogenic diet — is a low-carbohydrate diet, where your body uses fat for fuel. By removing almost all carbohydrates, and inserting healthy fats in their place, your body enters an advanced fat-burning condition called nutritional ketosis. Once in ketosis, your body will start using fat for energy, rather than carbohydrates or glucose.

There are a number of ways to shift into nutritional ketosis. The most important is cutting out the carbs. The standard American diet recommends consuming between 200 and 300 grams of carbohydrates per day. By contrast, keto usually involves eating 20 grams of carbohydrates throughout the day. While the keto diet is certainly high in healthy fats – cutting the carbs is actually the most critical step to getting in (and staying in) ketosis. Before we dive into specifics, we need to understand exactly how keto works.

How the Keto Diet Works

In a normal American diet, carbohydrates are consumed in abundance. Once eaten, carbs turn into glucose. Glucose can be thought of as the simplest form of sugar, and it is easy for the body to convert and use as your primary source of energy. Thus, glucose is your main source of fuel, at least when consuming the standard American diet. As a lot of carbs are consumed, your body has a rise in blood sugar, as these carbs are turned into glucose. Then, your body creates insulin, which is a hormone meant to transport glucose throughout your body. You may have heard the term ‘insulin spike’ – this is what that term refers to.

As your body uses this glucose, any extra is stored. This reserve of energy sounds good – until you release its stored as body fat. If you keep eating carbohydrates, your body will continually use glucose as its fuel source. This may seem beneficial, but in reality, it means you can’t dip into your fat stores. This leaves you in a state of constantly storing excess energy, which leads to weight gain. Meanwhile, you are unable to dip into your fat stores, so you can’t burn off any fat. 

But luckily for those who follow the keto diet, the only way to start burning off those fat stores, is by removing carbohydrates entirely. In turn, this diminishes your glucose stores (usually called ‘glycogen’). At this point, your body essentially realizes it is running out of energy, so it starts dipping into its reserves of fat. And there you have it – how keto burns off your stored body fat, and ramps up your metabolism.

Keto and Your Thyroid

There is a huge amount of misinformation out there about a keto diet’s impact on your thyroid. The truth is, keto lowers T3, which is the thyroid marker hormone. T3 is in some ways working against your body at higher levels, as it causes your cells to use more energy. Hence, a reduction in T3 is beneficial. Scientists think that a lowering of T3 will reduce free radical production and may even lead to a longer life. T4 is another important part of thyroid function, and it works with T3 to keep your body temperature, heart rate, and metabolism in proper ranges. Again, it is easy to see why the misinformation is out there, but the truth is far different. Keto positively impacts your thyroid, as well as positively impacting nearly every relevant biomarker of your health.

Keto and Cortisol

Cortisol is the body’s ‘stress hormone,’ and while it is commonly perceived in a negative light, it actually performs many helpful tasks which are essential for the body. For example, when you need to do an intense workout, cram for an important exam, or if you have to ward off a burglar – cortisol is critical for these processes to happen. However, it is easy to see how too much of this hormone could cause problems. You don’t always want to be on the edge of excess energy – for starters, how would you sleep? Cortisol dysregulation is a root cause of many health problems, and it’s important that you keep your cortisol in check, if you want to be optimally healthy. A keto diet is high in good fats, and moderate in protein, which makes your cortisol happy. By not having peaks and valleys of sugar rushes and crashes, your body is better able to stay in homeostasis. 

Keto and Your Exercise Routine

keto diet and excersise

Following a good exercise routine is required for any positive health outcomes, and keto is no different. But when it comes to hormonal issues, it is also easy to go too far into the red, and exercise too much. If you overtrain, you can quickly throw your hormones out of whack – especially cortisol. The most common occurrence as it relates to keto is attempting to do high-intensity interval training (HIIT) too often. If you are in ketosis, doing HIIT more than three times per week may do you more harm than good.  Just as your body needs exercise, your body also needs rest. 

Keto and the HPA Axis

The hypothalamic-pituitary-adrenal axis is critical for your overall health. You can think of the HPA axis as the nexus of the universe, at least in terms of your internal health. The hypothalamus puts out hormones and works with the adrenal and pituitary glands to keep everything running smoothly. When you start following a ketogenic diet, you may find an improvement with HPA axis function, as the data shows keto may improve hypothalamic stimulation. Other interesting research shows that ketosis may actually use a different metabolic pathway than normal glucose signaling, which may be part of why the keto approach is so effective. Hypothalamic neuropeptides are also elevated when following a keto diet, which means your HPA axis should be humming along smoothly – as long as you stay in ketosis.

Keto and Undereating

Perhaps surprisingly, there are many keto dieters who simply do not eat enough. This is likely due to the hunger blunting effects of the diet. It is important to track your calories when you first start the keto approach, to make sure you are giving your body what it needs. If you are not used to eating a diet low in carbs and high in fat, you will likely feel full when your body still needs more calories. Another potential problem with undereating comes from intermittent fasting (IF). While fasting is a great way to optimize your health, you cannot do it every day. It’s simply too much stress on your hormones and body. It is imperative that you track your food intake aggressively when you practice intermittent fasting. And be sure not to overdo it – think about the long term, not the short term.

Keto and Your Period

The menstrual cycle is a fickle thing. There are many, many different factors that can impact your period, as well as your premenstrual symptoms (PMS). Keto has actually been shown to have positive impacts on your period. In some cases, if you’ve had irregular periods for a long amount of time, you may find yourself getting back into a normal menstrual cycle when following a ketogenic diet. Some keto dieters also report increased flow, but this typically only happens in the beginning stages of adopting the diet. Once your body adapts to keto, things should go back to normal. The bottom line is that a ketogenic diet should only have a positive impact on your period. If you are experiencing issues with your menstrual cycle, consult with your doctor immediately, as it is likely that there are more serious issues going on.

In Conclusion

A keto diet should positively impact your hormones – not negatively impact them. Scientific research has shown benefits for thyroid health, as keto helps to lower T3 levels. With this lowered level, you can function better, as well as reduce free radical production. You may even live longer as a result. Scientific data has also shown cortisol levels drop when following a proper ketogenic diet. While cortisol is a very necessary hormone, it must stay in safe ranges. Ketosis helps to make this happen – and it also does a great job at helping you achieve other health goals.

The keto approach has a positive impact on your weight and fat loss goals, and can even lead to incredible physical and mental changes. However, it is important to not overtrain. You must exercise smartly, as well as eat responsibly, for truly optimal health outcomes. A ketogenic approach helps to keep your HPA axis in an optimal range, and actually may improve its overall functioning. If you are following keto, it is also crucial to make sure you are consuming enough calories. Undereating typically results in poor hormonal results, and can also lead to a laundry list of other health problems. A keto diet also has positive impacts on your menstrual cycle. If you believe you are experiencing hormonal issues of any kind, it is important to consult with your doctor.

The Best Way to Measure Your Ketones

Until now, there has not been a convenient and reliable way to check your ketones. That’s why we invented the first and only clinically- backed ketone breath monitor. By simply breathing in our device, you will have a reliable measurement of your current ketone levels in seconds, allowing you to track ketone changes all day. No more urine strips, no more pricking your finger – just a fast, easy and reliable breath test. You can bring our device with you to the office, take it to the gym – you can truly check your ketones anywhere. Unlike previous devices, which were often poorly made, unreliable, and not backed by clinical research – our ketone breath monitor has a patented deep lung sampling technique, a requirement for accuracy.. This means no other device is legally allowed to use our exclusive technology. Whether you are brand new to keto and want a convenient and reliable way to check your ketone levels, or you’re an elite level biohacker – Biosense is the perfect way to measure your ketones.

You don’t need to worry about continually buying strips, continually pricking your finger – we have all you need, in just one device. One of our favorite features is the personalized insights you get with the device. Every time you measure, your results are graphed and stored, so you can easily track your progress. Until now, there has not been an easy and convenient way to check your ketone levels – which has made many people give up on the keto diet entirely. But that outcome is no longer necessary, as we’ve made a device that does all the work for you. Just simply take one breath into the device, and within seconds you’ll know your ketone level. Whether your goal is to burn fat, lose weight, or improve your blood sugar – we have the answer.


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