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When she picked up clean eating and exercise habits back in college, Alison Hager was determined to shape up her body and reverse the 226-pound reading she saw on the scale. She took a personal training class, logged what she ate (no crash dieting), and began regularly working out — hard.
But even with an active lifestyle and chicken breast on the menu, Alison was still gaining weight. “My trainer knew something was up,” says Alison. “He suggested that I get everything checked out at the doctor’s, especially my thyroid.” Alison’s first blood test, which included a thyroid check, came back as squeaky clean as her lunches. But a gut feeling led her to seek out a second opinion, especially when her hair began falling out, her skin became dry as an alligator, her period stopped, and her body started to constantly feel cold as an ice cube.
Alison’s new doctor found that her thyroid hormone levels were way off, diagnosed her with hypo-thyroidism (or underactive thyroid), and put her on a small dose of medication. She focused even harder on eating well, balanced her training with cardio and weights, and eventually lost more than 90 pounds.
Small But Mighty
So how the heck could one small, unassuming butterfly-shaped gland at the lower part of her neck have such a huge impact on Alison’s health and fitness? As she learned, it’s a powerful little organ. “Your thyroid not only affects your metabolism, but it also affects many other things, like your heart rate, cholesterol levels, body weight, digestion, energy levels, muscle function, fertility, menstrual regularity and mood,” says endocrinologist Elizabeth Pearce, MD, associate professor of medicine at Boston University School of Medicine.
Regular workouts and a clean, nutrient-rich diet are two of your best tools for maintaining healthy thyroid function. A lean body goes a long way.
The thyroid’s job, specifically, is to produce and balance two hormones in your body: thyroxine (T4) and triiodothyronine (T3). When the balance is off and the thyroid cannot produce enough hormones, doctors refer to it as hypothyroidism (underactive thyroid). On the other hand, hyperthyroidism (overactive thyroid) occurs when your thyroid produces too much hormone. And when it comes to pursuing fit goals, both conditions spell trouble, says Pearce.
With an underactive thyroid, you’re more likely to gain weight (and hold on to it), feel fatigued and cold, and have irregular and/or heavy periods. Overactive thyroid is often characterized by weight loss, jitters, fatigue, tremors and heart palpitations. Both conditions are more common among women than men, and both are linked to heart disease. Either your heart beats faster (hyper) or beats more slowly and has to work harder (hypo), Pearce explains.
Active But Skinny Fat?
Sometimes you can do everything right in terms of diet and exercise, but if your thyroid isn’t functioning properly, you can still find yourself gaining weight, feeling weak during workouts and, ultimately, losing muscle. This was true for Julie Borscht, now 40, who, after having three kids, found herself “skinny fat,” exhausted and cranky. It wasn’t until she saw a specialist (an endocrinologist) that she finally got on the right dosage of thyroid medication, learned about how she should be eating (more frequent, protein-packed meals), started building muscle through weight training, and lost 20 pounds.
Your Healthy Thyroid Plan
Studies show that women with a BMI over 40 have a slightly lower thyroid function, says Pearce, but it’s not clear which is the cause and which is the effect. “The relationship between weight and thyroid function isn’t simple,” she says. But there is some evidence from a 2013 European Journal of Endocrinology study that links obesity to the development of thyroid cancer. Your best bet? Maintain a healthy weight with clean eating and exercise.
Maintain Iodine Levels
Iodine deficiencies (most common in women of childbearing age) are strongly linked to thyroid disorders. Table salt has been iodized in the U.S. for decades for this reason. But the obvious problem? Sodium is linked to health risks such as high blood pressure and cardiovascular problems, so you shouldn’t rely on your shaker. What’s more, the sea salt most popular with active women isn’t one of the types that are iodized. So what should you do? You can find iodine in seafood (fish, shellfish and sea vegetables such as kelp), some dairy products, and plants grown in iodine-rich soil. The American Thyroid Association has even recommended that women who are pregnant, breastfeeding, or planning to get pregnant should take a daily supplement of 150 micrograms of iodine, but check in with your doc first to evaluate your needs and risks.
Hit The Gym
With obesity, it’s not clear if a slow metabolism affects your thyroid, or if your thyroid causes your metabolism to slow. But one thing scientists do know: your metabolism slows with age, says Stella Lucia Volpe, PhD, RD, professor and chair of the department of nutrition sciences at Drexel University. “The only way to really increase it is with an exercise program that builds muscle tissue.” Weight training and interval training are terrific ways to build muscle, which is especially true for sluggish metabolisms like Alison’s. “I have to keep shocking my body every day. I can’t stick with the same workout and the same old cardio,” she says.
Treat Iron and Zinc Deficiencies
While getting enough iron and zinc can’t prevent thyroid disorders, for women who have underlying thyroid issues, treating deficiencies may help, explains Volpe. “Zinc and iron help convert T4 to T3 (the more active form), which your body needs for metabolic processes. Because of this, iron and/or zinc deficiencies have been linked to hypothyroidism,” she says, adding that any visit to the doctor to check the thyroid should also involve checking iron and zinc levels. The research in this area is still preliminary, so you may have to ask your doctor for additional tests.
Balance Female Hormones
Researchers suspect that estrogen is the reason thyroid disorders are more common in women. In Alison’s case, her body was releasing too much estrogen, which can hamper the conversion of T4 into T3, and lead to hypothyroidism. Estrogen levels fluctuate greatly during childbearing years, so talk to your OBGYN about things you can do to balance your hormones, such as changing your diet and reducing your exposure to environmental risk factors like pesticides, which may disrupt hormone function.
Though the science is still shaky, learning to zap stress may also help keep your thyroid in shape. “There is a belief that autoimmune disorders, such as a thyroid disorder, are more likely to occur following severe stressors, but we haven’t been able to prove it,” says Pearce. Evidence is mostly circumstantial and tied more closely to Grave’s Disease (caused by an overactive thyroid) than to hypothyroidism, “but reducing stress is a good tip in general for staying healthy,” says Pearce. Try this simple two-minute fix: close your door, turn down the lights and get into child’s pose; stretch your arms out in front of you while breathing deeply.
Thyroid disorders may not be preventable, since genetics appear to play a huge role, as do autoimmune disorders, but they are treatable, and there are steps you can take to help keep your body’s most powerful little gland in top shape.
Should You Get Tested?
The American Thyroid Association recommends that women over 35 have a blood test to detect thyroid problems every five years, even if they don’t have symptoms. No one else has made the recommendation, says Elizabeth Pearce, MD, associate professor of medicine at Boston University School of Medicine. “Everything around thyroid screening is controversial, but it’s reasonable advice,” she says. The most sensitive test is the thyroid-stimulating hormone (TSH) test. “If that comes back abnormal, other tests are performed,” she says. Other tests include T4 tests, T3 tests and an antibody test. If you have any of the following symptoms, see your doctor.
- Feeling cold
- Excessive dry skin
- Feeling forgetful
- Feeling depressed/experiencing mood swings
- Period irregularities
- Weight gain
- Feeling fatigued and sluggish
- Nervousness and anxiety
- Brittle or thinning hair
- Difficulty sleeping
- Increased perspiration
- More frequent bowel movements
- Period irregularities
- Unexplained weight loss
- Muscle weakness in the arms and legs
- Racing heart
- Hand tremors