Actor Paul Bettany's cocaine addiction as a youth has made him so wary of addictive substances he refuses to drink coffee. The WIMBLEDON star, who battled substance abuse during his teenage years, knows his mind is only in full control in the absence of any illegal drugs, alcohol or caffeine. He recalls, "That was the start of a really bad time. My drug use is long in the past. "Slowly I learned there was no point in destroying myself. "I can't work under the influence of anything now, not even caffeine."