Regular and fermented milk have similar galactose content
The authors suggest that the effect of milk on mortality is due to the milk sugar galactose. However, Hettinga, in his rapid response, stated that ‘the galactose intake from fermented dairy … is equal to the galactose intake from regular dairy’ (www.bmj.com/content/349/bmj.g6015/rr/778979).
Inspection of publicly available databases confirms that fermented milk and yoghurt contain appreciable amounts of galactose and its precursor, lactose.The Swedish Livsmedelsdatabasen shows 3.8 g/100g for disaccharides (presumably lactose) in fermented milk and 4.9 g/100g in regular milk. Databases which provide actual lactose and galactose numbers, such as the Dutch, US and UK tables, show even smaller differences between regular milk on the one hand and yoghurt and buttermilk on the other hand.
Thus the authors’ galactose hypothesis is not based on solid data.
Competing interests: No competing interests