Why it’s helpful to get a glucose level test

Skeletal formula: Pngbot. Design: BOOST Thyroid.

Skeletal formula: Pngbot. Design: BOOST Thyroid.

Glucose is the most important sugar that fuels your body. Usually more complex carbohydrates from your diet need to be broken down into glucose through digestion. 

Glucose and your thyroid

Glucose levels are regulated by thyroid hormones, particularly in your brain, where lower levels of thyroid hormones cause slower glucose metabolism (1-3).

Glucose blood values

Typically glucose levels in your blood are between 80 mg/dL–120 mg/dL. For the majority of healthy individuals, normal blood sugar levels are between 4.0–6.0 mmol/L (72–108 mg/dL) when fasting and up to 7.8 mmol/L (140 mg/dL) two hours after eating (4, 5).

When should you have a glucose test?

Ask your doctor for a glucose test if you have the following symptoms:

  • Excessive thirst

  • Frequent urination

  • Fatigue

  • Blurred vision

What can affect glucose test results?

Pregnancy, kidney disease, and a high number of red blood cells can affect a glucose test read-out (6).

Consuming simple sugars

You should always limit your sugar intake—which includes artificial sweeteners. Sugar substitutes affect the immune system and have been linked to decreased thyroid activity. One research study found that after a Hashimoto’s patient eliminated their previously high intake of artificial sweeteners, their thyroid stimulating hormone  (TSH) and antibody levels stabilized (7).

Track your glucose blood values and more in a free to use BOOST Thyroid app.


  1. Bianco AC, et al. Biochemistry, cellular and molecular biology, and physiological roles of the iodothyronine selenodeiodinases, 2002

  2. Constant EL, et al. Cerebral blood flow and glucose metabolism in hypothyroidism: a positron emission tomography study, 2001

  3. Bauer M, et al. Brain glucose metabolism in hypothyroidism: a positron emission tomography study before and after thyroid hormone replacement therapy, 2009

  4. McMillin JM. Blood Glucose, 1990

  5. Güemes M, et al. What is a normal blood glucose, 2016

  6. Barreau PB, et al. Effect of hematocrit concentration on blood glucose value determined on Glucometer II, 1988

  7. Sachmechi I, et al. Autoimmune Thyroiditis with Hypothyroidism Induced by Sugar Substitutes, 2018