Fatigue and Other Symptoms - Depression, Thyroid Hormones, ?

Hello. Thank you Barbell Medicine team for all of the information that you guys put out; it has really helped me out. I am looking for some guidance about what to do about the issues that I have been having.

Some background on me: I’m 19 years old, 6ft 1.5in tall, about 177lbs, and have a waist circumference of about 32in, at about 12% body fat. Over the past couple of years, I have been focusing on diet and training to lose body fat and gain muscle and strength. Once I am satisfied with my body fat percentage (probably around 10%), I plan on maintaining for a bit and then slowly gaining weight back. Around three years ago, I was about 195lbs and probably around 25% body fat. I am also a college baseball player. I am currently eating about 2100 calories a day with 170 grams of protein, generally lower fat (15-20% of calories), and plenty of fruit and vegetables. I sleep about 8 hours a night. I squat 315 for 5, deadlift 365 for 5, and bench 160 for 5. I am also a very strong student and a high achiever in school, going to a very demanding college.

For the past few years, I’ve been experiencing constant daily fatigue, brain fog, mild headaches, and trouble concentrating. I have also been depressed for most of this time. On June 8th of this year, I started being treated for depression, starting on Prozac at 25mg/day, then 50mg/day after two weeks at 25mg/day; I have been taking that for about 9-10 weeks now, but have not noticed any improvement. About two weeks after changing to 50mg/day, I had a range of labs done to check for physical causes of my symptoms. Results of note from the labs are below:

Total cholesterol - 203 mg/dL
LDL cholesterol - 124 mg/dL
Non-HDL cholesterol - 137 mg/dL
TSH - 1.90 mIU/L
Total T4 - 4.5 mcg/dL
Total T3 - 51 ng/dL
Everything else was essentially normal. Also, the labs unfortunately did not include free T4 or T3, and I also took a vitamin containing Biotin the night prior, which I know can affect the thyroid tests in particular.

Based on the T4 and T3, combined with my symptoms, my primary care doctor started me on Levothyroxine 50mcg/day on July 31st. My father was diagnosed with hypothyroidism about 10 years ago, and I also had some other symptoms that pointed towards it for myself, such as feeling cold often, having trouble losing weight, dry scalp, and high cholesterol despite a healthy lifestyle.

I then saw an endocrinologist, who ordered more labs and stopped me taking the Levothyroxine exactly two weeks after I had started it; he said this was because the TSH was normal, and so he did not believe I should be on the medicine. I got the new labs exactly two weeks after stopping the Levothyroxine, and I did not take any vitamins in that period. Results of note from the second round of labs are below:

Total cholesterol - 198 mg/dL
LDL cholesterol - 118 mg/dL
Non-HDL cholesterol - 133 mg/dL
TSH - 3.15 mIU/L
Total T4 - 4.4 mcg/dL
Total T3 - 67 ng/dL
Free T4 - 0.9 ng/dL (range 0.8-1.4, so barely normal)
Free T3 - 2.1 pg/mL
Antithyroid peroxidase antibodies - 5 IU/mL (range <9 IU/mL)
Anti thyroglobulin antibodies - <1 mIU/mL
Everything else was again essentially normal.

I then saw another endocrinologist, who said that they don’t believe that my problem is from the thyroid or a pituitary issue based on the TSH and free T4 being normal, despite the low values of total T4, total T3, free T3, and barely in range free T4. I am checking the TSH, free T4, and free T3 again using a new lab, as well as with a cortisol test to check for a possible adrenal condition, but the endocrinologist seemed doubtful that these would turn up anything different. They did not recommend any treatment at this time.

Sorry for the long background, but I wanted to be thorough. So, my questions are about what to make of the situation now.

  1. Is it common to have low levels of thyroid hormone but not have a problem in the thyroid or the system controlling it, and why would this be happening?
  2. Given that the issue is not with the thyroid, what other causes should I look into for my symptoms? Our current approach is to try treating the depression differently.
  3. Should I look to try a different type of antidepressant than Prozac, which has not seemed to have any positive effect, such as Wellbutrin?
  4. Could it be that treating the depression alone will relieve the hypothyroid symptoms, or even raise the thyroid hormone levels?
  5. Would there be any reason to try taking both T3 and T4 replacement to see if they help me to feel better? The endocrinologists I have seen have pushed back against this, but I know that some people have seen results.
  6. Is there any reason why my cholesterol would be high despite living a healthy lifestyle with good diet, exercise, and sleep? Most of the doctors have not been too concerned with this, but I’m curious as to why I may be seeing this result.

Thank you for taking the time to read about my situation, and I truly appreciate any help that you can offer me.

Hey Danny,

These are questions better suited for your physicians, as we cannot provide medical guidance here. That said, a few thoughts:

  1. It does not appear that there’s any abnormal thyroid function here.
  2. There are many potential causes of fatigue and certainly depression including depression itself driving some the fatigue. This needs to be sussed out by a physician using the appropriate workup, however.
  3. I cannot comment on this specifically other than to say that based on 93 randomized trials and >20,000 patients with unipolar major depression, all second generation SSRI’s (including fluoxetine, e.g. prozac) have roughly the same efficacy. Asking your physician about treatment options is certainly reasonable.
  4. It does not appear that you have hypothyroid-specific symptoms or hypothryroidism.
  5. Again, I cannot comment on what you should specifically do in this situation. That said, treating depression with thyroid medication in addition to SSRI does not appear to work better than SSRI + placebo with respect to response or rate of response.
  6. Yes, dietary habits such as saturated fat (high) and fiber intake (low), laboratory test variance, genetic causes, etc. though again, I cannot provide specific medical advice to you here. I would ask for clarification from your doctors, thought it is not recommended to draw a lipid panel while investigating hypothyroid in those with normal TSH levels.