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Ramadan is a sacred time for observant Muslims, who fast from dawn to sunset during this holy month. This period of fasting can, however, have various effects on the health of individuals, including those with pre-existing medical conditions. In this article, we will explore the impact of Ramadan fasting on people with hypothyroidism.
For those unfamiliar with Ramadan, it’s a month-long religious time when observant Muslims abstain from all food and liquids, including water, from sunrise until sunset. During Ramadan, most people who participate eat two average-sized meals per day—the evening meal eaten immediately after sunset, called Iftar, and one just before dawn, called Sehur.
There is no fixed date for Ramadan because it follows the Islamic calendar based on the lunar calendar. The exact dates for the start of Ramadan can also vary depending on the start date of the lunar month and the location.
In the U.S., in 2024, Ramadan is expected to start on March 11th; in 2025, the start date is February 28th or March 1st; and February 18th in 2026. Over time, Ramadan can fall during any of the four seasons, so the duration of daily fasting can range from around 11 to as many as 18 hours, depending on the season and where you live.
One aspect to consider during Ramadan fasting is the potential impact on thyroid hormone levels. Fasting can lead to specific metabolic changes, including alterations in thyroid hormone production. Several studies have reported that fasting during Ramadan can lead to changes in thyroid function, such as a significant increase in thyroid-stimulating hormone (TSH) levels in patients taking levothyroxine. Any type of fasting – including during Ramadan – is also associated with several changes to thyroid function, including:
- A slowdown in the conversion of T4 to T3
- Lower T3 levels
- Increased Reverse T3 levels
The disrupted eating schedule during the month of Ramadan can affect your gastric motility and circadian rhythm. This, in turn, can potentially impair deiodinase activity – the enzymes that convert T4 into T3 -- which can cause low T3 levels and symptoms including fatigue and brain fog.
While these changes are temporary and usually resolve within 2 to 3 months after Ramadan, a significant minority of people exhibit more pronounced and clinically relevant changes, especially those with higher TSH levels.
It is important to note that the effect of Ramadan fasting on hypothyroidism may vary among individuals. You might experience minimal disruption to your thyroid function or could potentially require closer monitoring during the fasting period. Your healthcare provider can play a crucial role in ensuring your well-being during Ramadan.
Fasting induces various hormonal changes, including changes in thyroid hormone levels. A study on dietary composition and fasting-induced changes observed an increase in both total and free T4 levels and a decrease in total and free T3 levels following fasting. These changes can have implications for individuals with hypothyroidism, as alterations in T3 and T4 levels can affect the metabolic rate and overall health.
Intermittent fasting has also been studied for its effects on the hypothalamus-pituitary-thyroid (HPT) axis, which is crucial in regulating thyroid function. An animal study showed that fasting can downregulate the HPT axis function, potentially hindering weight loss efforts in obese patients. This suggests that fasting has complex effects on thyroid hormone regulation, which could be particularly relevant for individuals with hypothyroidism.
Hypothyroid patients should consult their healthcare provider before Ramadan begins. Healthcare providers can adjust the timing and dosage of medication to ensure it is convenient and safe to take during fasting.
Some recommended timeframes for taking thyroid medication during Ramadan include:
- One hour before Sehur
- Two to four hours after Iftar
- Taking your medication right before bedtime
- Dividing your dosage to be taken before and after fasting hours
Also, remember that thyroid hormone replacement medication is generally better absorbed into the bloodstream while fasting compared to non-fasting periods. If you are taking a medication that includes T3, or you are particularly sensitive to your thyroid medication, this improved absorption can potentially cause temporary symptoms of overtreatment, including tremors, heart palpitations, rapid heart rate, excessive sweating, anxiety, and faster digestion. If you experience symptoms of overmedication, contact your healthcare provider for additional guidance.
It is vital for people with hypothyroidism who are observing Ramadan to be mindful of thyroid health and take steps to ensure you are supporting their thyroid function during fasting. Some tips to help maintain your thyroid health during Ramadan include:
Hydrate adequately
Make sure to use non-fasting hours for hydration. Keeping well-hydrated with sufficient fluid intake is crucial for supporting thyroid function for several reasons. When adequately hydrated, the body’s temperature regulation is more effective, energy levels are higher, and fatigue is reduced. The thyroid gland depends on proper hydration to maintain the balance of these hormones and ensure optimal bodily functions.
Eat nutrient-dense foods
Eating foods that provide essential vitamins and minerals for thyroid health is important. Nutrient-dense foods for hypothyroidism include:
- Vegetables: such as leafy greens, carrots, and peppers, which are high in antioxidants and fiber
- Fruits: like berries, apples, and bananas, which are low-calorie and high in nutrients
- Lean proteins: including fish, chicken, and turkey, which provide essential amino acids and minerals like selenium and zinc
- Nuts and seeds: such as Brazil nuts, macadamia nuts, and pumpkin seeds, which are rich in selenium and other beneficial nutrients
Regular monitoring
Monitor your thyroid hormone levels regularly with a healthcare provider to ensure proper function. The effects of any Ramadan-related changes in your thyroid levels can be mitigated when identified and treated quickly. Monitoring typically involves blood tests to measure thyroid-stimulating hormone (TSH), free thyroxine (free T4), and free triiodothyronine (free T3).
Keep in mind that if you’re hypothyroid and you’re fasting for Ramadan while pregnant, are over 65, or have osteoporosis, diabetes, or other chronic diseases, you should be monitored frequently as your thyroid function can significantly impact your health.
Consider thyroid-supportive supplements
Hypothyroid patients who are fasting should consider thyroid-supportive supplements to help improve thyroid function and hormone levels. Certain vitamins and minerals, such as selenium, zinc, iron, and B vitamins, may help enhance hypothyroid treatment and relieve symptoms of low thyroid. For example, selenium is needed for thyroid hormone production and helps protect the thyroid from oxidative stress, while zinc improves T3 levels significantly.
However, it’s important to note that excessive intake of certain supplements, such as iodine, may negatively affect thyroid health, so working with a healthcare practitioner to determine the specific needs and ensure a healthy and safe plan is essential.
Rest and stress management
Getting enough rest and managing stress levels are essential for your thyroid health. Chronic stress and fatigue can disrupt the delicate balance of thyroid hormones, leading to conditions such as hypothyroidism or hyperthyroidism. Stress can affect the thyroid by influencing the HPT (hypothalamic-pituitary-thyroid) axis, inducing thyroid autoimmunity, and impacting the production and conversion of thyroid hormones.
Overall, for patients with hypothyroidism, fasting during Ramadan can have an impact on thyroid function, particularly if you are taking thyroid hormone replacement therapy. The changes in mealtimes and the associated hormonal adjustments, particularly regarding the thyroid function and the HPT axis, suggest that fasting can both positively and negatively affect thyroid health. While the effects are generally modest and transitory, some patients may experience more pronounced changes.
If you’re hypothyroid and considering Ramadan fasting, it’s important to consult with your healthcare provider so they can carefully monitor your condition during and after Ramadan and adjust your treatment and medication dosage based on your specific needs.
Paloma Health can help you support your thyroid health during Ramadan. Paloma’s thyroid test kits make it easy to monitor your thyroid function from the convenience of home. Paloma’s Daily Thyroid Care supplement provides thyroid-supporting vitamins and minerals in one capsule. And Paloma’s experienced practitioners and nutritionists can work with you to create a plan for managing your hypothyroidism during fasting. With proper care and attention to treatment, nutrition, and hydration, you can support your thyroid health during Ramadan.
Vedrana Högqvist Tabor, Ph.D., contributed to this article.