Intermittent Fasting (IF) has gained popularity as a weight loss strategy, blending modern scientific research with age-old practices that date back to ancient Greece. Ever wondered why or how IF may be beneficial to individuals with a not-so-ideal thyroid condition like hypothyroidism? We shall unfold this mystery for you in this blog post.
Winding the Clock to When Meals Were Seldom
Intermittent Fasting is a pattern that echoes ancient times when our ancestors had to wait hours or even days to find their next meal. It is unlike diets that restrict particular food groups, instead, it challenges the conventional notion of three meals per day, thus readjusting our eating behavior.
Through IF, you might fast for 16 hours followed by an 8-hour window of eating, known as the 16/8 method. You could alternatively opt for partitioning your week, where you eat for five days and fast for two non-consecutive days, known as the 5:2 method.
Decoding the Language of Intermittent Fasting
To simplify the different fasting schedules, we have categorized them into four broad types:
1. Alternate-Day Fasting: This method involves eating normally one day and fasting the next. This pattern repeats every other day, creating a regular cycle of fasting and eating days throughout the week.
2. Time-Restricted Feeding: This plan utilizes a 24-hour cycle divided into durations of eating, followed by fasting, (like the 16/8 method).
3. Periodic Fasting: This method involves fasting on specific, non-consecutive days within a week. For example, with the 5:2 method, you eat normally for five days and fast on two non-consecutive days.
4. Long-Term Fasting: This plan includes fasting for two or more consecutive days.
Interestingly, even during the fasting periods, there are no objections to consuming no-calorie beverages like water, black coffee, or tea, and on certain plans, a minimum caloric intake is permissible.
Intermittent Fasting and Its Impact on the body
While religious practices form one of the reasons why some people fast, the primary driver behind the popularity of IF among health-conscious people is arguably weight loss. Scientific studies suggest that when we cease eating for several hours consecutively, hormones within our body adapt and start converting fat into energy, which invariably leads to weight loss. But keep in mind - excessive eating during non-fasting periods could erode your weight loss gains.
Besides weight loss, some initial research shows that the bonuses of IF extend further, to include:
1. Managing inflammation, in the context of chronic ailments like arthritis
2. Reducing insulin resistance, especially among those with type 2 diabetes
3. Enhancing cardiovascular health by helping improve blood pressure and resting heart rates
4. Improvements in thinking and memory - with likely benefits in Alzheimer's disease
Unveiling the Risks of Intermittent Fasting
Despite the multitude of benefits IF offers, there are inherent risks too. For instance, unforeseen eating disorders could emerge from its practice. Further, people with existing health conditions such as heart disease are at risk as fasting might exacerbate their problems. A study of over 20,000 adults found that those who followed an 8-hour time-restricted eating schedule, a type of intermittent fasting, had a 91% higher risk of death from cardiovascular disease. Those with diabetes are especially at risk of hypoglycemia (low blood sugar), a potentially critical condition. Further, some medications used to treat type 2 diabetes need adjustment for time-restricted eating. Therefore, people considering intermittent fasting should speak with their healthcare provider before changing their eating patterns.
Additionally, certain specific population segments are advised against undertaking IF:
1. Children
2. Athletes requiring endurance
3. Underweight Individuals
4. Women who are pregnant, breastfeeding, or attempting conception
5. Individuals at risk for malnutrition due to potential vitamin deficiencies
For a subset of people, IF might be more harmful than good. It is a good idea to speak with your healthcare provider before making any significant changes to your dietary patterns, especially if you have any medical conditions.
Decoding the Relationship Between the Thyroid and Intermittent Fasting
The thyroid gland plays a key role in your body's metabolism. Its operations can be directly influenced by fasting. Some studies have presented that fasting leads to a decrease in the levels of thyroid-stimulating hormone (TSH), triiodothyronine (T3), and/or thyroxine (T4) -- key elements involved in the thyroid hormone cycle. It's important to first delve into how your body regulates the generation of these hormones. TSH is responsible for prompting your thyroid to produce and release both T3 and T4 hormones. Your body ensures these hormones exert their metabolic influence by activating T3. When this delicate balance in your thyroid hormone production is disrupted, thyroid disorders can occur, leading to an increase or decrease in TSH levels, affecting the balance of T3 and T4.
According to a study by Rand T. Akasheh et al. (2019), alternate-day fasting (ADF) and daily calorie restriction (CR), both resulted in similar weight loss in individuals with subclinical hypothyroidism (a condition where your lab tests indicate that you have an underactive thyroid but you don’t have any symptoms).
The Effect of Hypothyroidism, Hashimoto’s on Intermittent Fasting
Hashimoto’s thyroiditis can lead to hypothyroidism, an autoimmune thyroid disorder. The autoimmune aspect implies that your immune system begins to mistakenly damage your healthy thyroid cells, impacting their hormone production and triggering chronic inflammation.
The main treatment option for Hashimoto’s disease focuses on supplementing your body with the necessary thyroid hormone and thus normalizing your TSH levels. There is research aimed at reducing inflammation in Hashimoto’s that might improve patient well-being. IF may help achieve this goal in the following ways (Patterson et. al, 2015):
1. Optimizing gut microbiome: IF can potentially boost beneficial gut bacteria. These changes in gut bacteria are shown to have beneficial effects in certain autoimmune conditions.
2. Lowering oxidative stress: IF can help increase protective proteins, thereby reducing oxidative stress.
3. Reducing inflammatory biomarkers: IF has been shown to help lower several inflammatory biomarkers.
How Intermittent Fasting Influences Thyroid Hormone Medications
Those with diagnosed hypothyroidism or Hashimoto’s may require medication to help manage their symptoms and maintain their thyroid hormone levels within a normal range. The jury is still out on how IF affects your dosing routine, but some studies suggest changes may be necessary.
One particular study noted that after fasting during the month of Ramadan, TSH levels exceeded the normal range. This suggests that during periods of fasting, the dosage of thyroid hormone medications may need to be adjusted (Sheik et al, 2018). If you are someone with hypothyroidism on treatment with thyroid hormone medication, please consult your healthcare provider before you decide to try out any IF plans. Also, be vigilant for any new symptoms or worsening of existing ones, and promptly report them to your healthcare provider.
Note from Eureka
Before you board the train of IF for its health benefits, Eureka recommends talking to your healthcare professional. This holds especially true if you're under thyroid hormone replacement medication management. At Eureka, you'll receive comprehensive care for hypothyroidism that includes an expert practitioner and the option to work with a thyroid nutritionist. By working closely with a nutritionist, you'll be able to make eating plan adjustments that will further enhance your thyroid health. Simultaneously, Eureka’s nutritionist can also help reverse nutritional deficiencies and assist with weight loss. If you think this could benefit you, take the first step and schedule an appointment today! And remember, we at Eureka also offer free advice on improving your thyroid health.
Remember, everyone's fasting experience may differ, and for some, it may provide benefits beyond weight loss. However, it is essential to monitor and adjust individual health needs and consult a practitioner whenever necessary.
References
- 8-hour time-restricted eating linked to a 91% higher risk of cardiovascular death. American Heart Association Epidemiology and Prevention|Lifestyle and Cardiometabolic Health Scientific Sessions 2024, Abstract P192. Read more.
- Weight loss efficacy of alternate day fasting versus daily calorie restriction in subjects with subclinical hypothyroidism: A secondary analysis by Rand T. Akasheh et al. (2019). This study found that alternate day fasting (ADF) and daily calorie restriction (CR) produce similar weight loss in individuals with subclinical hypothyroidism without affecting thyroid hormone levels. Read more.
- Intermittent Fasting and Human Metabolic Health by R. Patterson et al. (2015). This paper provides an overview of the health benefits and risks associated with intermittent fasting, including its effects on thyroid function. Read more.
- Impact of Ramadan Fasting on Thyroid Status and Quality of Life in Patients with Primary Hypothyroidism: A Prospective Cohort Study from Karachi, Pakistan. Sheikh, A., Mawani, M., & Mahar, S. A. (2018). Read more.
