n seven of the 13 EU countries studied in the report, Denmark came out on top for caffeine consumption with 33 per cent of consumers exceeding the 400 mg limit.The Netherlands followed at 17.6 per cent and Germany at 14.6 per cent.The French, despite the Gallic coffee culture, came at a surprisingly low 5.8 per cent.Of all the respondents, about one third of the adults were regular consumers of energy drinks with 12 per cent of those guzzling them down four or five days a week.But alarmingly for regulators, a whopping 68 per cent of 10- to 18-year-olds were regular users of energy drinks with 12 per cent of them heavy consumers.Caffeine levels in energy drinks can vary greatly, the agency said, between about 70 mg a litre to 400 mg.