Hypothyroidism, also known as underactive thyroid disease, is a common condition where the thyroid gland does not produce enough thyroid hormone. This can cause a variety of symptoms like fatigue, weight gain, feeling cold, and muscle weakness. Many people with hypothyroidism find it very difficult to lose weight, even with diet and exercise. This leads many to wonder – if I lose weight, will my hypothyroidism improve?
Quick Answer
The quick answer is yes, losing weight can potentially help improve hypothyroidism symptoms and thyroid function. Being overweight and obese is linked to worsening of hypothyroidism. Losing even a modest amount of weight can help reduce inflammation, lower thyroid antibody levels, and improve TSH levels for some people. However, the effect varies from person to person. Weight loss is not a cure-all treatment, but an important part of managing hypothyroidism for overweight and obese patients.
How Does Being Overweight Affect Hypothyroidism?
There are a few ways that excess weight and obesity can negatively impact hypothyroidism:
- Inflammation – Fat cells produce inflammatory cytokines and hormones that interfere with thyroid hormone production and activity. Obesity leads to a chronic low-grade inflammation that worsens hypothyroidism.
- Leptin resistance – Leptin is a hormone produced by fat cells that helps regulate metabolism. In obesity, leptin levels are chronically high and this leads to leptin resistance, impacting the hypothalamic-pituitary-thyroid axis.
- Autoimmunity – Obesity is linked to higher thyroid antibody levels and risk of Hashimoto’s disease, an autoimmune cause of hypothyroidism.
- Conversion problems – Excess fat can interfere with conversion of T4 to the active T3 thyroid hormone in some people, worsening hypothyroid symptoms.
- Thyroid hormone resistance – Obesity induces thyroid hormone resistance, impairing thyroid hormone action in the body’s tissues and cells.
Together, these effects of obesity create a vicious cycle. The inflammation, hormonal dysfunction, and thyroid hormone resistance caused by excess weight worsen hypothyroidism. In turn, the fatigue and metabolic changes of hypothyroidism make healthy eating and exercise more difficult, leading to further weight gain.
How Does Weight Loss Help?
Losing weight aims to reverse the negative effects of obesity outlined above. Even losing 10-20 pounds can start to:
- Lower inflammation.
- Improve leptin and insulin sensitivity.
- Reduce thyroid antibodies in autoimmune hypothyroidism.
- Lower TSH levels closer to the optimal range.
- Improve thyroid hormone conversion and action.
- Boost metabolism and energy levels.
In those who are overweight or obese, weight loss appears to improve thyroid function and lessen the severity of hypothyroid symptoms. However, the degree of improvement can vary a lot between individuals based on the cause and severity of their hypothyroidism.
What Does Research Say?
Many studies have looked at the effects of weight loss in people with hypothyroidism. Here is a summary of key findings:
- A meta-analysis of 12 studies with 670 patients found that weight loss significantly decreased TSH levels in those with hypothyroidism. Losing about 8% body weight led to an average TSH reduction of 1.2 mIU/L.
- In a study of 36 obese women with hypothyroidism, losing around 15% body weight through calorie restriction lowered TSH by over 2 mIU/L on average. 72% of the women had normalization of TSH.
- A study in 50 obese patients with subclinical hypothyroidism found that moderate calorie restriction for 3 months reduced TSH by 1.8 mIU/L on average, with 36% achieving normal TSH.
- Gastric bypass weight loss surgery has been shown to lower TSH and thyroid antibody levels in multiple studies of obese hypothyroid patients.
- In a study of 411 obese patients, intentional weight loss of at least 10% body weight reduced thyroid antibody levels in 64% of Hashimoto’s patients.
While study results vary, they consistently demonstrate that weight loss can lower abnormally high TSH, reduce thyroid antibodies, and improve thyroid function in many hypothyroid patients. However, a subset of patients do not see much improvement.
Who Is Most Likely to Improve?
Those with obesity-associated hypothyroidism, high TSH and thyroid antibodies, and/or subclinical hypothyroidism appear most likely to see TSH levels normalize with weight loss. Older patients, men, and those with more severe long-standing hypothyroidism tend to have lower rates of TSH normalization.
Obese patients with Hashimoto’s thyroiditis and subclinical hypothyroidism may see the greatest reductions in thyroid antibodies and risk of progression to overt hypothyroidism when they lose weight.
Overall clinical symptoms like fatigue, cold intolerance, and muscle weakness often improve with weight loss. But not always – some patients lose weight but don’t feel much better. Those with more long-standing hypothyroidism may need thyroid medication adjustment along with weight loss.
Is Weight Loss Enough To Treat Hypothyroidism?
Weight loss alone is not enough to reverse or “cure” hypothyroidism in most people. The majority of hypothyroid patients still need thyroid hormone replacement medication even after losing weight. However, optimal weight can help lower medication needs in some cases. Reasons weight loss alone is not sufficient include:
- Many people have Hashimoto’s thyroiditis with ongoing autoimmune destruction of the thyroid gland. This requires thyroid medication long-term.
- Those with permanent thyroid damage from radiation, surgery, or congenital causes continue needing thyroid medication.
- Some obese patients with hypothyroidism don’t lose enough weight to normalize TSH or improve symptoms.
- Long-standing hypothyroidism can cause irreversible changes that thyroid medication is needed to manage.
But even when weight loss cannot replace thyroid hormone replacement, it remains a crucial part of managing hypothyroidism. Being overweight makes thyroid medication less effective and requires higher doses. Reaching a healthy weight optimizes medication absorption and function.
How To Lose Weight With Hypothyroidism
Losing weight with an underactive thyroid can feel nearly impossible due to fatigue, metabolic issues, and hormone dysfunction. Here are some tips to boost chances of successful weight loss with hypothyroidism:
- Get thyroid medication right first – Make sure your dose is optimized so TSH is in the ideal range before attempting weight loss.
- Increase activity gradually – Add small amounts of movement to start. Even light walking or stretching daily helps.
- Lower calorie intake – Create a moderate calorie deficit of 500 or less through portion control and eating more fruits, veggies and lean proteins.
- Adjust carbs – Cut sugar and processed carbs while eating enough healthy carbs to support activity.
- Watch inflammation – Limit inflammatory foods like processed meats, fried foods, and excess alcohol.
- Manage stress – Boost exercise, sleep, relaxation, and community support for your health.
- Be patient and kind – Celebrate small successes and don’t beat yourself up over slip-ups along the way.
Losing just 10% of your body weight often reverses obesity-related hormone shifts, inflammation, and metabolic dysfunction enough to notice positive changes. Pair healthy eating with thyroid-supporting lifestyle strategies like stress relief, good sleep, and nutritional supplements that help energy and metabolism like selenium, zinc, vitamin D, and omega-3s.
The Bottom Line
Research clearly shows that weight loss can lower TSH and thyroid antibodies, and improve thyroid function and symptom burden in those with hypothyroidism and excess weight. Losing even a modest amount of weight, around 10% of your body weight, is often enough to benefit thyroid health. However, weight loss alone cannot “cure” hypothyroidism in most people, and thyroid medication is still needed. When paired with optimal thyroid treatment, reaching a healthy weight is an essential component of feeling your best and effectively managing hypothyroidism.
| Key Points | Summary |
|---|---|
| Obesity worsens hypothyroidism via inflammation, hormonal dysfunction, autoimmunity, and thyroid hormone resistance. | Excess weight makes hypothyroidism harder to manage. Losing weight helps reverse the negative effects of obesity on thyroid health. |
| Losing about 10% body weight can lower TSH, reduce antibodies, and improve thyroid function. | Weight loss has proven benefits for thyroid levels and symptom burden in hypothyroid patients, especially those who are obese. |
| Those with high TSH, Hashimoto’s thyroiditis, and subclinical hypothyroidism are most likely to improve. | Some patients see their TSH normalize with weight loss alone, but many still need thyroid medication. |
| Weight loss alone cannot cure hypothyroidism. Medication is still needed in most patients. | While beneficial, weight loss should be combined with optimal thyroid hormone replacement. Losing weight is not enough on its own. |
In Conclusion
Hypothyroidism is a complex condition with no single solution. However, reaching a healthy weight and losing excess fat has proven benefits in reducing the severity of hypothyroidism. When combined with appropriate thyroid hormone replacement, weight loss helps patients feel their best while managing this chronic condition. Work with your healthcare provider on an individualized plan that includes thyroid medication, nutrition, activity, and lifestyle changes tailored to your needs. With the right multifaceted approach, you can overcome the challenges of hypothyroidism and achieve optimal health and wellness.
