In its report, the authority concludes that food supplements available on the Dutch market could contribute to caffeine levels exceeding reference intakes set by The European Food and Safety Authority (EFSA).
Referring to EFSA’s recommended levels for adults (200 mg per single dose and 400 mg per day) the report states, “Both the single dose intake and the total daily intake of caffeine resulting from only the use of food supplements could already exceed the respective reference values, independent of other dietary intake.
“Hence, a health risk by consumption of these food supplements cannot be excluded.”
The report, carried out by RIVM at the request of the Ministry of Health, Welfare, and Sport (VWS), identifies forty caffeine containing food supplements that are available in Dutch web shops.
Based on the caffeine content of these products and their recommended use, the RIVM estimated that the intake of caffeine through these supplements varied between 16 and 500 milligrams (mg) for a single dose and between 16 and 1000 mg for a daily dose.
For more than 25% of the supplements the amount of caffeine per single dose and/or recommended daily dose was not clear.
Assessment methods
The assessment involved a chronic dietary intake assessment for the general population in order to estimate the intake of caffeine from the diet (not including supplements).
In addition, food consumption data of the Dutch National Food Consumption Survey (DNFCS) of 2012-2016 were used along with caffeine concentrations of products compiled by EFSA.
Chronic exposure to caffeine was also calculated with values for adults amounting to 260 and 636mg per person per day at the P50 and P95, respectively, corresponding to 3 and 8 milligrams per kilogram body weight per day (mg/kg bw per day)
For adolescents (13-17 years), estimated intake levels were 35 and 174mg (1 and 3mg/kg bw).
A toxicological assessment was also carried out with reference values from EFSA (2015) used. For a single intake of caffeine, the reference value (RV-SI) is 200 mg.
The reference value for a habitual or daily intake (RV-DI) is 400 mg for adults and 3 mg/kg bw per day for adolescents.
Findings revealed that when adhering to instructions, 10 supplements led to a caffeine intake exceeding either the RV-SI of 200mg or the RV-DI of 400mg for adults. One brand exceeded both levels.
For adolescents, the investigative team found a total of 20 supplement brands that recommended a daily dose above the RVDI of 3 mg/kg bw.
Caffeine sources
“Therefore, a potential risk to consumers is associated with the consumption of these supplements and possible adverse effects cannot be excluded for part of the caffeine containing food supplements available in Dutch web shops,” the report says. “This does not consider the exposure to caffeine from sources other than food supplements.
Besides supplements, foods that contain caffeine include chocolate, coffee, tea and products in which these products have been processed, along with cola beverages and energy drinks.
The report concludes that for both Dutch adolescents and adults, caffeine intake via the use of caffeine -containing food supplements can greatly exceed the intake via the ‘normal’ diet.
In addition, the report’s authors add that this may result in intakes largely exceeding reference values for both adolescents and adults with a median and high intake via the diet.