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Walnuts are high in dietary fiber and on average contain 31 percent of your daily value of fiber per cup—this is great for your digestion and cholesterol, but could potentially alter the absorption of certain medications.

Be careful...if you take thyroid medication. Walnuts may decrease the absorption of levothyroxine, the medication most commonly used to treat hypothyroidism. Other dietary fiber supplements, as well as soybean flour, may also affect the function of levothyroxine.

**Note: This is not a complete list. You should always ask your doctor if you should avoid any particular foods, drinks or supplements specific to your medication regimen.