The importance of the small butterfly thyroid is often overlooked when it comes to general health. Many people suffer from chronic thyroid-related conditions such as hypothyroidism and Hashimoto’s disease. The ketogenic diet is known for providing a range of health benefits, but what about thyroid health? How does the keto diet affect your thyroid health and hormones? If you have thyroid disease, should you try a ketogenic diet? Let’s discuss keto, thyroid and research!
What is a Ketogenic Diet?
The keto diet is a high-fat, moderate-protein and low-carbohydrate eating pattern. If you’re wondering how to get started on a keto diet, a typical macro-nutrient ratio looks like this:
- 55 to 60% fat
- 30 to 35% protein
- 5 to 10% carbohydrate
For a standard 2,000-calorie diet, you want to aim for no more than 50 grams of carbohydrates per day. For reference, a bagel has about 50 grams of carbohydrates.
While cutting carbs may not sound as fun, there are some research-backed benefits to doing so. From helping to control blood sugar, to improving blood lipids, to helping to get rid of those pesky love handles, a keto diet is sure to have a positive impact on your health.
What is the Thyroid?
The thyroid is a gland located in the neck that is similar in shape to a butterfly or bow tie. It is difficult to feel the thyroid gland under normal circumstances, but if it is enlarged or develops a goiter (abnormal enlargement of the thyroid gland), your doctor can easily feel it.
Thyroid hormones are secreted from the thyroid gland. Thyroid hormones help control the rate of chemical functions in your body by increasing the amount of oxygen used in your cells and by stimulating body tissues to produce proteins.
Many of your important bodily functions are affected by thyroid hormones, including calorie burning rate, growth, heart rate, digestion, skin maintenance and fertility. As we age, the thyroid gland shrinks and moves down the neck.
The two types of thyroid hormones are T4 (thyroxine) and T3 (triiodothyronine).
Your thyroid gland produces the main thyroid hormone T4, which is only marginally useful in speeding up your body’s metabolic rate. T4 is converted in the liver and other tissues to T3, which is a more active hormone. Certain factors can affect this conversion process, such as illness and the needs of the body at the time.
How does a Ketogenic Diet Affect Thyroid Health?
There is a common belief that a ketogenic diet can negatively impact thyroid health, but this does not seem to be confirmed by enough research or even anecdotal stories. There is some research that suggests that calorie restriction, protein restriction and ketogenic diets can lower T3 levels, but more research is needed.
This reduction in T3 levels may actually be positive and beneficial when TSH and T4 levels are normal, and some evidence points to the body’s natural physiological adaptations to maintain muscle mass and achieve a deeper state of ketosis. The reduction in T3 allows for deeper ketosis and preserves muscle mass.
Interestingly, studies have linked lower T3 levels to longer life expectancy. Some people are overly calorie restricted on keto therapy, which has been shown to lower T3 levels. This may be a protective response of the body during periods of deprivation.
Lower T3 levels can lead to symptoms of hypothyroidism that are mistakenly attributed to the ketogenic diet. Make sure you are consuming enough calories on a ketogenic diet to prevent your T3 levels from dropping too low.
The thyroid may increase T3 production in response to the glucose in a high-carbohydrate diet. Consuming carbohydrates will increase your iodine needs because your thyroid needs more iodine to make more T3 to process carbohydrates.
How to Modify the Keto Diet for Thyroid Health without Leaving Ketosis?
Home lab testing gives you direct insight into the effects of a keto diet on your thyroid hormone levels. By tracking the effects of different adjustments on your blood work, you can find your optimal keto diet. Some of the adjustments you can make include:
- To use intermittent fasting
- To adjust the carb, protein, and fat ratios
- To reduce consumption of foods you may be sensitive to such as gluten, dairy, or soy
- To balance your lifestyle all around, including your sleeping pattern, exercise, and stress management
In just one month, you can see the impact of lifestyle changes on your thyroid hormone levels. Over time, you will be able to determine if keto is not for you, or find a modified keto pattern that works for you and get the results you want to see.
Thyroid hormones and thyroid disease are complex and depend on a variety of factors, such as nutrition. Many people with thyroid disease experience improvements and feel great on a ketogenic diet. The best thing to do is monitor how you feel on ketosis and see your doctor or healthcare practitioner if you have any questions or concerns, or if you experience any symptoms.
Overall, the keto diet appears to have a positive impact on thyroid health. Certain factors can negatively affect the thyroid and thyroid hormone production, for example
- Intense exercise
- Caloric restriction
- Lack of bile, pancreatic enzymes, and stomach acid
- Weight loss
Highly processed vegetable and grain-based oils like canola oil