Ratnayake WN, Swist E, Zoka R, Gagnon C, Lillycrop W, Pantazapoulos P. The American Journal of Clinical Nutrition. 2014;100:1036–40. doi: 10.3945/ajcn.113.078352
Canadians are becoming increasingly aware that trans-fats in certain foods are a health risk, especially with regard to cardiovascular health, or “heart health”. In Canada, efforts to reduce trans-fatty acids (TFAs) in foods include requiring that TFA content be shown on food labels and encouraging the food industry to voluntarily limit trans-fatty acid content in all vegetable oils and soft margarines to 2% of total fat, and in all other pre-packaged foods to 5% of total fat.
To assess the impact of these efforts, researchers at Health Canada measured the levels of trans-fatty acids in 639 breast milk samples collected as part of the MIREC Study. They found that the average trans-fatty acid (TFA) contents in total milk fat steadily decreased between 2009 and 2011, as shown in the following table:
| Year Samples Collected | Number of Samples | Avg. % of TFAs in Breast Milk Fat |
|---|---|---|
| 2009 | 153 | 2.7% |
| 2010 | 309 | 2.2% |
| 2010 | 177 | 1.9% |
Moreover, the drop in the trans-fatty acid content in breast milk was even larger when compared to data from 1992, when the average value in Canadian human milk was 7.2%.
There is further good news in relation to diet: the researchers found a large decrease in the consumption of trans-fatty acids among Canadian breastfeeding mothers between 2009 and 2011:
| Year | Estimated Consumption of TFAs |
|---|---|
| 2009 | 0.9% |
| 2010 | 0.5% |
| 2011 | 0.3% |
These estimated values are lower than the World Health Organization’s maximum recommended consumption value of 1% of total energy for a healthy diet.
These results suggest that the trans-fat labeling regulations in 2003 and recommendations by Health Canada in 2007 instructing food manufacturers and restaurants to limit trans-fatty acids in foods have resulted in substantial reductions in trans-fatty acids in the diets of Canadian breast-feeding mothers, and in their breast milk.