Challenges in Analysis of Vitamins in Dietary Supplements

Shira Rosencwaig, National Public Health Laboratory, MOH, Tel Aviv, Israel (shira.r@phlta.health.gov.il)
Nitzan Shy, National Public Health Laboratory, Moh, Tel Aviv, Israel

The National Public Health Food Laboratory has been analyzing vitamins content in multiple food types for the past two decades. These tests include quantification of vitamins B1, B2, B6, B12, C, D and folic acid in primarily infant formulae, both powdered and liquid, as well as enteral products and baby foods such as purees and cereals and other types of food.

In 2022, following a small survey of 40 samples, we began testing for vitamins content in various dietary supplement samples imported to Israel or manufactured locally.

Our well established and validated analytical methods were suited to quantify both endogenous as well as added vitamins in food matrices, yet these methods did not suit all dietary supplements, due to their unique formulations.

Not knowing the specific formulations of each tested product and having no information regarding the manufacturers’ methods of quantification of each of the vitamins, we embarked on a journey to first develop methods which were able to address specific products and then find a way to create general analytical methods to quantify vitamins content in both dietary supplements and foods.

Here we present our work which focused primarily on modifications in the sample preparation and extraction processes.