A mother's fat intake can impact infant infectious disease outcomes
Findings show types of fats matter when it comes to gut well-being
April 14, 2021
Science Daily/University of British Columbia Okanagan campus
A team of UBC Okanagan researchers has determined that the type of fats a mother consumes while breastfeeding can have long-term implications on her infant's gut health.
Dr. Deanna Gibson, a biochemistry researcher, along with Dr. Sanjoy Ghosh, who studies the biochemical aspects of dietary fats, teamed up with chemistry and molecular biology researcher Dr. Wesley Zandberg. The team, who conducts research in the Irving K. Barber Faculty of Science, explored the role of feeding dietary fat to gestating rodents to determine the generational effects of fat exposure on their offspring.
"The goal was to investigate how maternal dietary habits can impact an offspring's gut microbial communities and their associated sugar molecule patterns which can be important in immune responses to infectious disease," says Dr. Gibson, who studies gut health and immunity as well as causes of acute or chronic diseases like inflammatory bowel disease.
Their study suggests that the type of fat consumed during breastfeeding could differentially impact an infant's intestinal microbial communities, immune development and disease risk.
The three main classes of fatty acids include saturated (SFA), found in meats and dairy products, monounsaturated fats (MUFA), found in plant-based liquid oils, and polyunsaturated fatty acids (PUFAs), found in some nuts, fish and shellfish. PUFAs are further characterized as either n-3 PUFAs or n-6 PUFAs, based on the number and positions of double bonds in the acyl chain.
Previous research has determined both n-3 PUFAs and n-6 PUFAs can have a negative impact on intestinal infections such as Enteropathogenic E. coli, Clostridium difficile, salmonella and gastrointestinal illnesses from eating poorly prepared or undercooked food or drinking contaminated water. In contrast, diets rich in MUFAs and SFAs have been shown to be largely protective against these infections.
Dr. Gibson's latest research states the beneficial properties of milk fat, or saturated fats, during the pre-and postnatal period might improve protection against infectious intestinal disease during adulthood particularly when a source of n-3 PUFAs are combined with saturated fats.
"Our findings challenge current dietary recommendations and reveal that maternal intake of fat has transgenerational impacts on their offspring's susceptibility to intestinal infection, likely enabled through microbe-immune interactions," says Dr. Gibson.
Global consumption of unsaturated fatty acids has increased significantly between 1990 and 2010, she adds, while people are consuming lower amounts of saturated fats during pregnancy because of recommendations to reduce saturated fat intake.
"Although it has been known for decades that high-fat diets can directly alter inflammatory responses, recent studies have only just begun to appreciate how fatty acid classes may have discrete effects on inflammation, and can shift host responses to an infection," says Dr. Gibson.
Dietary fatty acids can impact inflammatory processes including defensive inflammatory responses following an intestinal infection. This can affect the severity of disease, making dietary fatty acids an important consideration in predicting disease risk, Dr. Gibson explains.
Researchers believe it's a combination of dietary fat-host interactions with the intestinal bacteriome that can determine the severity of these infections. The intestinal bacteriome, Dr. Gibson explains, is established during infancy and plays a critical role in aiding immune system maturation and providing a barrier against colonization with potential pathogens.
And Dr. Ghosh notes this latest research suggests current health guidelines should be reevaluated.
"Currently, Canadian dietary guidelines recommend nursing mothers replace foods rich in SFA with dietary PUFAs, with an emphasis on consuming n-6 and n-3 PUFAs," Dr. Ghosh says. "Given that PUFAs worsened disease outcomes in postnatal diet studies, in our views, these recommendations should be reconsidered."
While breast milk protein and carbohydrate concentrations remain relatively inert, fatty acid contents vary considerably and are influenced by maternal fat intake.
"Overall, we conclude that maternal consumption of various dietary fat types alters the establishment of their child's bacteriome and can have lasting consequences on their ability to respond to infection during adulthood," says Dr. Gibson. "At the same time, we show that maternal diets rich in SFA, provide a host-microbe relationship in their offspring that protects against disease."
It's important to understand that the intestinal bacteriome is established during infancy because it plays a critical role in aiding immune system maturation which can provide a barrier to potential pathogens, explains Dr. Zandberg. He also notes a healthy bacteriome is dependent on early-life nutrition.
"Sugars decorate important proteins in the gut," says Dr. Zandberg. "Their patterns are altered in the offspring due to the dietary choices of the mother during gestation and lactation. The change in patterns is associated with changes in the ability of the infant to fight off infectious disease in our model."
https://www.sciencedaily.com/releases/2021/04/210414100121.htm
Study firms up diet and depression link
October 10, 2018
Science Daily/James Cook University
In an unusual experiment, researchers have found that among Torres Strait Islander people the amount of fish and processed food eaten is related to depression.
A JCU research team led by Professors Zoltan Sarnyai and Robyn McDermott looked at the link between depression and diet on a Torres Strait island, where fast food is available, and on a more isolated island, which has no fast food outlets.
Dr Maximus Berger, the lead author of the study, said the team interviewed about 100 people on both islands.
"We asked them about their diet, screened them for their levels of depression and took blood samples. As you'd expect, people on the more isolated island with no fast food outlets reported significantly higher seafood consumption and lower take-away food consumption compared with people on the other island," he said.
The researchers identified nineteen people as having moderate to severe depressive symptoms: sixteen were from the island where fast food is readily available, but only three from the other island.
"People with major depressive symptoms were both younger and had higher take-away food consumption," said Dr Berger.
The researchers analysed the blood samples in collaboration with researchers at the University of Adelaide and found differences between the levels of two fatty acids in people who lived on the respective islands.
"The level of the fatty acid associated with depression and found in many take-away foods was higher in people living on the island with ready access to fast food, the level of the fatty acid associated with protection against depression and found in seafood was higher on the other island," said Dr Berger.
He said it was important to remember that contemporary Western diets have an abundance of the depression-linked fatty acid (n-6 PUFA) and a relative lack of the depression-fighting fatty acid (n-3 LCPUFA).
"In countries with a traditional diet, the ratio of n-6 to n-3 is 1:1, in industrialised countries it's 20:1," he said.
Professor Sarnyai said depression affects about one in seven people at some point in their lives and Aboriginal and Torres Strait Islander people are disproportionately affected by psychological distress and mental ill-health compared with the general population.
"Depression is complex, it's also linked to social and environmental factors so there will be no silver bullet cure, but our data suggests that a diet that is rich in n-3 LCPUFA as provided by seafood and low in n-6 PUFA as found in many take-away foods may be beneficial," he said.
Professor Sarnyai said with the currently available data it was premature to conclude that diet can have a lasting impact on depression risk but called for more effort to be put into providing access to healthy food in rural and remote communities.
"It should be a priority and may be beneficial not only to physical health but also to mental health and wellbeing," he said.
https://www.sciencedaily.com/releases/2018/10/181010093645.htm