by Caitlin Beale, MS, RDN May 25, 2021 3 min read

Your thyroid, the butterfly-shaped gland found at the base of your neck, is the body's metabolic master. It helps regulate every process in the body — from the number of calories you burn to your internal thermometer, heart rate and even your digestive tract. So when it isn't working optimally, your body will start to send signals that something is off.

What Are Common Low Thyroid Symptoms?

An under active thyroid is very common, affecting nearly five out of every hundred people in the U.S., with women being more likely to be diagnosed than men.

There are a number of key hormones involved in thyroid function. Your hypothalamus in the brain releases thyroid-stimulating hormone (TSH), which tells your thyroid gland to make Thyroxine (T4). Triiodothyronine (T3) is also produced by the thyroid gland, but in much lower amounts than T4. Because T3 is the active form, and mostly what the body uses metabolically, an important conversion process that converts T4 into active T3 needs to happen.

Thyroid symptoms occur when these hormones are no longer at optimal levels. A common reason for an imbalance can be linked to the body not being able to convert the hormone into its active usable form (T3), or that thyroid receptors become resistant to the hormones, affecting the signaling pathways.

Without our master metabolism regulator working well, everything slows down, causing symptoms like:

  • Moodiness and irritability
  • Weight gain, or difficulty keeping weight off
  • Cloudy thinking
  • Constipation
  • Sleep issues
  • Higher cholesterol levels
  • Hair thinning
  • Fatigue
  • Dry skin
  • Fertility issues

What Are Possible Causes of Low Thyroid?

The problem is that many low thyroid symptoms are subtle, making them easy to overlook. It's often not until symptoms start to compound that you realize something is off. Unfortunately, this delay also allows for certain lifestyle factors that could be causing the issue to go unaddressed.

So what are the possible root causes? While every person's experience is different, low thyroid function can be caused by a a range of factors from nutrient deficiencies and increased stress to poor gut health. Unresolved issues in the gut are one of the most common issues that can impact the thyroid. This is because approximately 80% of the immune system resides in the gut, and gut bacteria play a key role in converting T4 into T3.

Deficiencies in the diet — from micronutrients to antioxidants — can also be a reason for a sluggish thyroid. Certain nutrients like iodine and iron are necessary for optimal thyroid health and hormone production. These deficiencies can be related to food choices and can be further compounded by poor gut health.

Lifestyle Factors to Address Low Thyroid

Fortunately, lifestyle changes can reduce symptoms and help bring your body back to a state of balance.

Nutritious natural ingredients in shape of thyroid. Healthy food containing vitamins and minerals

As a first step, you can start to rebalance your hormones with thyroid supporting foods such as pumpkin seeds, sunflower seeds, Brazil nuts, dark leafy vegetables, mushrooms, lima beans, and certain types of wild caught seafood. These foods and more provide key sources of thyroid supportive minerals such as iodine and selenium.

Next, it's essential to understand your lab values. By doing a Functional Medicine lab test at home, you can look at exactly where you stand when it comes to the key hormones that impact stress, mood and metabolism. Based on these results, you can address hormone imbalances that may be interfering with your body's ability to achieve optimal thyroid levels.

If you feel overwhelmed or are not sure where to start, a comprehensive educational program that outlines and explains all aspects of thyroid health can help give you the confidence you need to understand the reasons behind any imbalance and empower you to take control over your body and your health.

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