Not washing your hands after working in the garden or playing in the woods – that may at first sound like dirt and dust, but is actually good for your health. Again and again, scientists advocate coming in contact with naturally occurring bacteria intentionally in order to maintain a healthy bacterial balance and diversity, in particular on the skin and in the gut. This diversity, the so-called microbiota, is extremely important for our wellbeing and health.
In case of the gut flora a diet sufficiently high in fibre plays a crucial role. US scientists have found that merely switching to a fibre-rich diet will not fully restore a good gut flora. An already reduced bacterial diversity is passed on from generation to generation.
According to a report in the scientific journal “Nature”, researchers fed two groups of mice harbouring a human gut microbiota. One group was given a diet rich in fibre, the other one which was low in fibre. Within a few weeks, the animals receiving low-fibre feed showed reduced bacterial diversity and lower numbers of specific bacterial strains. Afterwards, the mice were returned to a high-fibre diet and the gut flora recovered, yet only partially. Amounts of some bacterial species continued to remain lower.
When the mice had offspring, it was found that this incomplete gut flora was passed on and continued to decline from generation to generation. Only a faecal transplant – i.e. transferring the original, diverse gut flora – and a simultaneous return to a high-fibre diet resulted in a fully restored bacterial diversity.
Our decision whether to let good natural bacteria into and onto our bodies may hence also impact on our progeny.