Health information is often ineffective in motivating health-behaviour change. One way to improve information effectiveness might be to highlight autonomy, which is associated with less defensiveness and more adaptive psychological functioning. Three studies assessed whether experimentally elevating autonomy led to adaptive responses to risk information about alcohol consumption. In Study 1 (N = 104), participants completed either an autonomy prime or a neutral prime task and read either risk information about the dangers of alcohol consumption or neutral information. Among high-risk participants in the autonomy prime condition, those who read risk information reported greater autonomous motivation towards moderate alcohol consumption than did those in the neutral information condition. Study 2 (N = 157) compared two types of autonomy prime tasks with a neutral condition. For high-risk participants who read risk information, the autonomy prime tasks elicited greater autonomous motivation, more positive attitudes and greater intentions to drink in moderation than did the neutral prime task. Study 3 (N = 130) found that for high-risk participants who read risk information, autonomy prime participants reported less subsequent alcohol consumption than did neutral prime participants. The results are discussed in terms of the benefits of autonomy for adaptive responses to risk information.