There's a yogurt on the market in Japan that contains the health-promoting bacteria Bifidobacterium animalis subsp. Lactis LKM512 – known for short as LKM512.
When lab animals are given the bacteria they live longer, say researchers at the Kyodo Milk Industry company.
LKM512 is not a newcomer. Mitsuharu Matsumoto and Yoshimi Benno, two Japanese researchers have been publishing articles on the organism since 2001. The bacteria makes elderly people's gut healthier [FEMS Immunol Med Microbiol. 2001 Oct; 31(3): 181-6.], reduces the chance of gut cancer in healthy people [Mutat Res. 2004 Dec 21; 568(2): 147-53.], and also helps against eczema [Clin Exp Allergy. 2007 Mar; 37(3): 358-70.] – if the publications are anything to go by. Japanese ads proclaiming the benefits of the bacteria are common, like the one shown below.
In August 2011 the researchers published the results of an animal study in the prestigious PLoS One. The article is even more impressive than their previous publications on LKM512. In the study the researchers compared a group of mice that were given the bacteria in their food for their whole life with a group that received standard feed. The mice in the LKM512 group lived to a considerably older age, and the researchers noticed the effect after just 15 weeks.
As they aged, the mice that got LKM512 developed fewer tumours and fewer ulcers. These symptoms are common in the type of mouse the Japanese used, as they age.
The photos on the left above show a piece of the gut of 45-week-old mice. The intestine of the mouse that had had LKM512 was in better shape than that of the mouse in the control group. The figure on the right shows the activity of genes in the gut of 45-week-old mice in the control group [Control], in mice of the same age that had been given the bacteria [LKM512], and in the gut of young mice that had not been treated [Younger]. The bacteria makes the gut cells' DNA function as if the cells were still young.
The researchers suspect that the bacteria keep the gut young, and that younger intestines produce more polyamines. These enter the blood and extend life expectancy through their anti-inflammatory effect. [Med Hypotheses. 2011 Oct; 77(4): 469-72.]
PLoS One. 2011;6(8):e23652.