Survey of caffeine levels in hot beverages
Thursday 29 April 2004
Food Survey Information Sheet 53/04
- In 2001 the Agency advised pregnant women to limit their intake of caffeine to less than 300 mg per day in light of research that indicated that caffeine intakes above this may be associated with low birth weight and, in some cases, miscarriage.
- This advice included information on the number of beverages that equate to 300 mg of caffeine. The advice was based on caffeine levels in teas and coffees prepared under laboratory conditions according to standard procedures.
- The aim of this survey was to gather data on the level of caffeine in teas and coffees made by consumers following their usual procedures.
- 400 samples of teas and coffees prepared by consumers were collected from family homes, workplaces or purchased in retail settings from 10 areas across the UK.
- All drinks were analysed to determine the concentration of caffeine per serving i.e. per cup or mug.
- A wide variation of caffeine levels (excluding decaffeinated samples) were observed:
- tea ranged from less than 1 mg to 90 mg of caffeine per serving (mean 40 mg)
- instant coffee ranged from 21 mg to 120 mg of caffeine per serving (mean 54 mg)
- ground coffee ranged from 15 mg to 254 mg of caffeine per serving (mean 105 mg)
- Statistical analysis showed that there was a positive trend between the reported perceived strength of samples (weak, medium and strong) and the level of caffeine per serving.
- The mean caffeine levels determined in this survey confirm that the levels quoted in the Agency’s previous advice to pregnant women are appropriate. The information gained will also be used to refine future estimates of caffeine intake.