If It's Not My Thyroid Then What Is It?


Fatigue, weight gain, mood swings, poor concentration, memory issues, sweating, heart palpitations – your internet search says these are all symptoms of thyroid disease…but what happens when thyroid blood tests are actually normal? At Atlanta Endocrine Associates, Dr. Scott Isaacs is a thyroid expert and offers accurate diagnosis and state-of-the-art treatment. To learn more, contact the office in Atlanta, Georgia

Should the doctor prescribe thyroid hormone to improve symptoms despite lack of evidence of a thyroid disorder? The answer is no. Current thyroid laboratory testing is overly sensitive and specific for thyroid disorders, so when the laboratory tests are normal, thyroid disease is highly unlikely and another cause of symptoms should be sought. Furthermore, taking thyroid hormone for symptom relief in the absence of thyroid disease may cause dangerous irregular heart rhythms and bone loss. It is important to recognize that there are many non-thyroid causes of thyroid-like symptoms and recognizing additional signs may help you and your doctor work together to make the correct diagnosis.

Heart Disease

While no one would miss chest pain or shortness of breath as signs of coronary disease and heart failure, there are other more subtle signs that mimic thyroid disease and should never be dismissed. Palpitations are often associated with an overactive thyroid however, these fast and/or irregular heartbeats may also occur with heart failure or valve disorders. Fatigue is also a sign of coronary disease or heart failure, the latter causing weight gain due to accumulation of fluid in the tissues, which may be seen as swelling, also known as edema. Although pain in the neck or jaw may be seen with certain types of thyroiditis, those are worrisome symptoms for angina or heart attack, and may be accompanied by sweating or nausea. Prompt diagnosis of heart disease limits further damage to heart muscle and disability.

Sleep Disorders

Many patients associate their fatigue with an underactive thyroid, but fatigue is a prominent symptom of sleep apnea, a common disorder that affects over 30% of men and over 15% of women. Recognition of clues like non-refreshing sleep, excessive sleepiness during the day, drowsy driving, irritability, depression, poor concentration, and memory loss may help you to bring this to your doctor’s attention. It is important to diagnose and treat sleep apnea – left untreated it may cause high blood pressure, stroke, coronary artery disease, heart failure and atrial fibrillation. Other sleep problems like narcolepsy, idiopathic hypersomnia, insomnia, shift work disorder, or even being awakened by light or noise may cause daytime fatigue. Prompt identification and resolution will help provide more restful sleep.

Liver or Kidney Disease

Liver and kidney problems can cause fatigue, dry skin, swelling in the legs and ankles and loss of appetite. Laboratory tests may show elevated creatinine for kidney disease or elevated liver enzymes (AST-aspartate aminotransferase, ALT-alanine aminotransferase). 75-100 million Americans have a common condition known as fatty liver disease which can be a cause of chronic fatigue. Fatty liver disease is caused by a buildup of fat in the liver and is related to increased body fat, genetics, and the environment. The diagnosis of fatty liver disease is suspected with abnormal liver tests (although liver tests can be normal) and confirmed with an imaging study such as an ultrasound, CT, or MRI scan.

Vitamin and Mineral Deficiencies

Vitamin and mineral deficiencies are a common cause of symptoms that can be like thyroid disease. These symptoms include fatigue, aches, and pains, dry or flaking skin, cracks in the corners of the mouth and numbness in the extremities. Vitamin B12 and vitamin D are the most common vitamin deficiencies although there can be many others, especially with people who don’t eat enough vegetables and fruits. Vitamin B12 deficiency is more common in people who eat a vegetarian or vegan diet. Iron is the most common mineral deficiency. Iron deficiency is caused by either blood loss (such as a bleeding ulcer, colon polyp, heavy menstruation) or malabsorption (caused by intestinal disorders). Vitamin and mineral deficiencies can be identified with blood tests done by a primary care physician or endocrinologist.

Blood Disorders

Disorders of red or white blood cells can mimic thyroid disorders with symptoms like fatigue, weakness, feeling cold, excessive sweating, pale skin, easy bruising, shortness of breath, leg cramps, difficulty concentrating, dizziness and insomnia. Low red blood cell counts, also known as anemia, can be caused by iron deficiency or vitamin B12 deficiency, but there are many other causes. Leukemia is a type of bone marrow cancer that produces cancerous white blood cells and can come on slowly (chronic leukemia) or suddenly (acute leukemia). The diagnosis of blood disorders is made with a test called CBC for complete blood count.

Neurologic Disorders

Fatigue is one of the most common symptoms of neurologic disorders. These include multiple sclerosis, Parkinson’s disease, stroke, traumatic brain injury and myasthenia gravis. There may be accompanying symptoms such as muscle weakness, abnormal skin sensations, headache, constipation, tremor, or slow movements. If you suspect that you could have a neurologic disorder, it’s a good idea to check in with your primary care physician or a neurologist.


It’s a well-known fact that depression has physical symptoms, many of which are identical to thyroid disease. The most common symptoms of depression are vague aches and pains. Other symptoms include back pain, joint pain, gastrointestinal problems, sleep disturbances, fatigue, weight gain or weight loss. Some patients with depression only have physical symptoms, making diagnosis a challenge. If all other medical conditions have been ruled out, it’s helpful to consider your mental health as a source of symptoms.

Medication Side Effects

Complaints of weight gain and fatigue should always prompt a search for thyroid disease, but when the laboratory tests are normal, a search for the cause of those symptoms should include the medicine cabinet. Medications causing weight gain include steroids, antihistamines, blood pressure medications, antidepressants, and diabetes medications. Fatigue can be caused by antihistamines, antidepressants, supplements (like melatonin), as well as by medications for high blood pressure, anxiety, pain, and even antibiotics. One medication reference lists over 1,000 medications that have fatigue as a side effect. Substances like caffeine and nicotine may cause palpitations and tremors, typical symptoms of an overactive thyroid, but fatigue is seen when the effects wear off. While not all medications in each class cause weight gain and/or fatigue, if you are concerned about one of your medications, you must discuss this with your physician prior to stopping any medication. It is potentially dangerous to stop a medication without a substitute treatment in place.


Along with ruling out serious medical conditions that cause hypothyroid symptoms, consider your lifestyle. Are you living optimally to promote health and wellbeing? An unhealthy diet, lack of adequate physical activity, dehydration or poor sleep can cause thyroid-type symptoms. A healthy lifestyle includes a nutritious diet plan that contains a lot of vegetables and fruits, daily physical activity, 1½-2 quarts of water and 7-9 hours of restful sleep. Over the counter sleep medications can worsen symptoms because of side effects like daytime sleepiness and weight gain. Instead of medication, try to have good sleep hygiene with consistent bedtimes, avoiding stimulating activities (like internet browsing or social media) before bedtime and have a dark, quiet bedroom. Excessive stress from family, job or finances can have physical symptoms that mimic thyroid disease, so it’s always helpful to find ways to reduce stress in your life. Excess alcohol use (more than 1 per day for women, 2 per day for men) can cause thyroid symptoms like fatigue and weight gain. Excessive caffeine can cause fatigue, racing heart and rebound headaches.


Non-traditional doctors and internet sites often tout undiagnosed thyroid disease or Hashimoto's disease as a source of a multitude of ailments. But there are many other conditions that can cause thyroid symptoms. If thyroid blood tests are normal a thyroid disorder is highly unlikely. Your doctor should monitor thyroid function tests periodically and refer you to an endocrinologist if necessary. Work with your physician to consider all the possibilities for your symptoms and focus on living a healthy lifestyle. by Scott Isaacs, MD and Cheryl Rosenfeld, DO If you’d like to learn more about other conditions that cause thyroid symptoms, please feel free to call us or schedule an appointment with Dr. Isaacs.