Chocolate and migraine

Double-blind studies

Three double-blind studies are reported in the 2020 review:

Study	People	Chocolate vs placebo	Result
Marcus 1997	63 with headache	60 g vs carob	No significant difference
Gibb 1991	20 with migraine	40 g vs carob-based placebo	41.7% had headache after chocolate, none after placebo
Moffett 1974	25 with migraine	44 g vs synthetic fat placebo	No significant difference

Reviewers read the Gibb result differently. The 2020 review states that the difference did not reach statistical significance. A 2003 paper called a small study of this kind a convincing link (Peatfield 2003). All three studies are old and small.

A separate review of oral challenge studies judged one study of phenylethylamine in chocolate as conclusive, and it found no effect on headache (Jansen 2003).

What people report

Across 25 prevalence studies, chocolate was named by 1.3% to 33% of participants, and two studies found no one who named it. Most relied on recall, which measures belief rather than a link between exposure and attack. In the one electronic diary study included, chocolate was named in under 1.5% (Nowaczewska 2020).

Craving or trigger

ICHD-3 lists cravings for particular foods among prodromal symptoms, which can occur hours or days before the headache. The Migraine Trust names sweet foods such as chocolate specifically. If you crave chocolate, eat it and get an attack, the order of events looks like cause and effect. The American Migraine Foundation says such an attack would have happened whether or not the craving was satisfied.

Testing this needs chocolate or placebo given independently of cravings, not eating to match a craving (Stubberud 2021). The double-blind studies above compared chocolate with a placebo, but they are small, and the review reports nothing on when cravings occurred.

Proposed mechanisms

These are theoretical. On the side of a trigger, proposed routes include flavanol-driven nitric oxide release, serotonin release and phenylethylamine. The review says existing studies have not confirmed the serotonin theory. On the protective side, the magnesium and riboflavin in chocolate and reduced CGRP release in laboratory studies have been proposed, but the review reports a lack of data showing a benefit of chocolate on migraine (Nowaczewska 2020).

How to check it in your diary

1. Log craving and eating as separate entries, each with a time.
2. Log other early symptoms the same day, such as yawning, tiredness or neck stiffness. If they came first, the chocolate is unlikely to be the start of the attack.
3. Count chocolate days with no attack. These days are easy to forget and are needed for the comparison.
4. Keep your window fixed. The American Migraine Foundation suggests linking a food to a headache only if it starts within 24 hours.

The 2020 review advises that doctors should not implicitly recommend that people with migraine avoid chocolate. The Migraine Trust says there is not enough evidence either way. If your diary points to chocolate, talk to your clinician before cutting out food groups. For the general method, see how to test a suspected trigger.