a coffee cup with hot coffee with lots of coffee beans

Q. I was alarmed to hear about the interaction of coffee and levothyroxine. I take this medication daily “upon rising” as my doctor instructed me.
I usually have a cup of coffee after 30 or 45 minutes. Does this mean I have been undoing the benefits of my medicine all this time? The only warnings I was given are to: take levothyroxine on an empty stomach and not to take it with magnesium or aluminum.
I drink three or four cups of coffee a day. My doctor checks my blood every six months and tells me to continue the medication at the same dosage because there has been no change in the level.
A. The Italian researchers who uncovered this interaction found that after an hour there was no problem (Thyroid, March 2008), but when coffee is drunk right around the same time that levothyroxine is taken, it can reduce the absorption of this thyroid hormone.
The most important point when it comes to taking thyroid medication is to be consistent, however, and you are doing that admirably. That is why your doctor has not found variations in your blood level of TSH (thyroid stimulating hormone), the indicator used to assess thyroid function. Our advice: keep doing what you are doing.
You may want to know more about other foods that could interfere with levothyroxine absorption, however. In addition to antacids containing magnesium or aluminum, people should avoid bran at the same time they take this thyroid medicine. Bran muffins or bran cereal could block absorption even more than coffee.
Taking minerals such as calcium, iron or zinc around the same time as levothyroxine can also interfere with proper absorption of the hormone (Thyroid, May, 2011). Chromium picolinate, which is sometimes used as weight loss supplement, also reduces levothyroxine absorption (Thyroid, Aug., 2007) One way to avoid such conflicts would be to take levothyroxine at bedtime (Archives of Internal Medicine, Dec. 13, 2010).
If you would like more information about this topic, you may be interested in our Guide to Thyroid Hormones. Please feel free to comment on your own experience.

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  1. eleanor
    hollywood, florida
    Reply

    i’m 87 – – take a seaweed vegetable complex & formula “thyroid esessentials” from swansons health products
    1 ‘t.e.’ at noon – 1 at night along with the seaweed – doing fine
    good to go with coffee in am without complications

  2. Esther
    Reply

    I am 84 years old and I started to take Actalin for my Thyroid. I didn’t think it was doing anything for me so I stopped taking it and went back to my Armour. I still get up 3 times in the night to use the bathroom, but I’m grateful that I can sleep. Every time I turn around something else is going wrong with my body. I just recently started with a new doctor and I really like her I think too many doctors just rely on what they learned in medical school and don’t continue their education. I hope this doctor will help me. I think this site is very helpful and I think everyone should try to get as much information on their own to assist their doctors.
    Susie

  3. Cheri
    Okla. City
    Reply

    Honestly, after reading all of this I’m not finding much clarity or comfort. I have been on Synthroid several years and per instructions, take first thing in the morning with a full bottle of water but have always believed the waiting period for coffee & food was a half hour, which seems like an eternity. I cannot even imagine having to wait longer or giving up my coffee with milk & honey.

    Does my little dab of milk in two cups of coffee fit into the same category as calcium? I am feeling so defeated with RA and my whole life revolving around what I can & cannot have & when. It is exhausting & confusing.

    Any clarity or encouragement will be so appreciated. I have considered exploring more natural remedies but according to my blood tests I appear to be in the normal range. That being said, I don’t really know if this was basic (lazy) testing or the T3/4??? Or whatever. So complicated and technical for this almost 70yr. Old Chickie.

    • Terry Graedon
      Reply

      As long as you are taking your thyroid medicine the same way every day, the dose can be adjusted. Yes, milk in your coffee contains calcium, and both the coffee and the milk could reduce the amount of Synthroid you absorb. Have you considered taking your thyroid pill at bedtime? Some people find that helpful.

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