Here's the quote from P.261 under the Halodrol profile, but repeated under the profiles for all oral steroids:
Studies have shown that taking an oral anabolic steroid with food may decrease its bioavailability (footnote #563). This is caused by the fat-soluble nature of steroid hormones, which can allow some of the drug to dissolve with undigested dietary fat, reducing its absorption from the gastrointestinal tract. For maximum utilization, this [as with all other] steroid should be taken on an empty stomach.
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