KEY POINTS:
Variations in nutrient claims on food labels are not a food safety concern, says the New Zealand Food Safety Authority.
Variations were expected as the level of nutrient on the nutrition panel was based on an average, authority assistant director (joint food standards) Jenny Reid said yesterday.
She was responding to concerns raised after studies comparing actual nutrient levels with those claimed on the labels of a variety of products found discrepancies.
Christchurch food scientist Barbara Thomson, from Environmental Science and Research, measured nutrient levels in 160 foods including baby food, cereal and fruit drinks and compared them with manufacturers' claims on labels.
She found glaring differences in levels of vitamin C, D and A, folate, calcium, iron and selenium.
Nearly 58 per cent of samples did not meet the label claims.
Green MP Sue Kedgley said the survey meant consumers could have no confidence in the accuracy of food labels.
"It appears that labels have become little more than a marketing tool for food producers, rather than a way of imparting accurate information to consumers. This is a serious concern."
But Ms Reid said a lot of factors would influence the levels in any single serving of food, including analytical methods, storage conditions and the fact that manufacturers needed to cater for possible degradation of the nutrient during its shelf life.
As part of its annual monitoring work, the authority commissioned research from Environmental Science and Research on fortification averages in the food supply.
This referred to the analytical levels of added nutrients in food versus the level stated in the Nutrition Information Panel.
Ms Reid said that in the past three years a series of studies had been carried out looking at the nutrient levels of 260 samples from nine different food groups. They included fruit drinks, baby food, bread and cereal.
The studies helped the authority undertake a risk assessment of the consequences of nutrient additions to foods, both mandatory and voluntary.
Of the foods tested, almost 58 per cent did not meet the label claims, with 15 per cent containing less than the stated level of nutrient and 42 per cent containing more.
Ms Reid said labels gave an average reading.
"Rather than tell you exactly what nutrients you will get from eating a food on one occasion, the labels give you a picture of the nutrients you will get from routinely eating that particular product."
Labels were indicative and useful tools in providing guidance for people who wanted to compare different products.
"They are not a blueprint of what someone is consuming on every occasion."
Ms Reid said a lot of nutrients were not stable and levels might be affected by the production process, shelf life and the conditions the product was stored under.
- NZPA