The findings, made by a team of British scientists, add weight to the emerging body of evidence that has suggested the same thing.
Diverse microbiomes have long been linked to a lower risk of diabetes, obesity and inflammatory gut diseases like colitis or Crohn’s.
How was the study carried out?
Nottingham University and King’s College London researchers examined the gut microbiome of 876 women for the study.
They tested the diversity and abundance of so-called ‘good’ bacteria against their dietary intake of omega-3 fatty acids – measured through questionnaires.
Blood serum levels, which indicate how much of the nutrient is in the blood, were also taken, the researchers said in the journal Scientific Reports.
OILY FISH TO PREVENT SCHIZOPHRENIA?
Eating oily fish while pregnant may protect children from developing schizophrenia when they grow older, new research suggested.
In trials on mice, scientists found mice deprived of omega-3 fatty acids in the womb displayed signs of the mental health disorder as adults.
The nutrient, abundant in salmon, mackerel and sardines, is already known to be good the brain – but the new study is the first to show a link to schizophrenia.
Japanese researchers also discovered similar effects for pregnant mice who had a lack of omega-6, found in mayonnaise, sunflower seeds and flaxseed oil.
Both nutrients change the way genes are expressed, a process called ‘epigenetics’, the scientists behind the landmark study believe.
What did they find?
They found that women who consumed more omega-3 and had higher serum levels had a more diverse gut microbiome.
Lead author Dr Ana Valdes, of Nottingham, said: ‘The human gut is receiving a lot of attention in medical research as it is increasingly linked to a wide variety of health issues.
‘Our digestive systems are home to trillions of microbes, most of which are beneficial in that they play a vital role in our digestion, immune system and even regulate our weight.
‘Our study is the largest to date to examine the relationship between omega-3 fatty acids and the composition of the gut microbiome.’
It is believed the good effects of omega-3 are derived from a specific bacteria the nutrient helps to produce.
N-carbamylglutamate (NCG) can be found in higher quantities in participants who consume more of the nutrient.
This bacteria has previously been linked to lower inflammation and a lower risk of obesity, the scientists said.
What else can omega-3 do?
Omega-3, which has also been shown to have anti-cancer properties, can also be found in mackerel, walnuts and chia seeds.
Other studies have shown the nutrient to have positive effects on decreasing high blood pressure, easing arthritis and preventing cognitive decline.
The British researchers were keen to stress that their findings were only true when participants had diets with plenty of fibre and probiotics.