People who eat a healthy plant-based diet are less likely to suffer from dangerous snoring caused by obstructive sleep apnoea (OSA), Flinders University sleep researchers say.
The new study, published today in the international journal ERJ Open Research, analysed the diets and sleeping patterns of thousands of people to find more risk of OSA and poor sleep among adults who regularly eat an unhealthy diet high in sugar, refined carbohydrates, starch and salt.
"This is one of the first large-scale analyses into the correlation between plant-based diets and sleep apnoea," says Flinders University College of Medicine and Public Health researcher Dr Yohannes Melaku.
"It reinforces suggestions that eating a healthy diet high in vegetables, fruit, whole grains and nuts will reduce the risk of OSA and associated conditions such as high blood pressure, type 2 diabetes and even heart attack and stroke. "
While risk factors for OSA may stem from genetics or behaviour, including diet, previous research has primarily focused on the impact of calorie restriction, specific dietary elements and weight loss.
"With this study, we wanted to address that gap in overall dietary patterns and explore the association between different types of plant-based diets and the risk of OSA."
The study found people with diets highest in plant-based food were 19% less likely to have OSA, compared with those eating diets lowest in plant-based food. Those eating a largely vegetarian diet were also at a lower risk.
However, people eating a diet high in unhealthy plant-based foods were at a 22% higher risk, compared to those eating low amounts of these foods.
The researchers also found differences in the risks for women and men, with a plant-based diet having a stronger correlation for decreased OSA risk in men and an unhealthy plant-based diet having a larger increased risk for OSA in women.
"This research doesn't tell us how diet changes the risk for OSA, but it could be that a healthy plant-based diet reduces inflammation and obesity. These are key factors in OSA risk," says Flinders University co-author Professor Danny Eckert, Director, Adelaide Institute for Sleep Health, Flinders Health and Medical Research Institute.
"Diets rich in anti-inflammatory components and antioxidants, and low in harmful dietary elements, can influence fat mass, inflammation, and even muscle tone, all of which are relevant to OSA risk."
The researchers now plan to investigate the links between eating ultra-processed food and OSA risk in the same group of people. They also intend to study the interaction between diet and OSA risk over the longer term.
The findings were based on an examination of data collected from 14,210 people who contributed to the US National Health and Nutrition Examination Survey - which included healthy, unhealthy and pro-vegetarian diet details compared with participants' responses to their OSA risk survey.
The experts at the Flinders Health and Medical Research Institute and Adelaide Institute for Sleep Health have given key insights into better sleep practices in the new Australian TV series, Sleep Revolution (SBS OnDemand), starting on 6 March 2024.
It's been estimated that up to 1 billion people aged 30 to 69 years worldwide suffer from mild to severe sleep apnoea, which heavy snoring is a common symptom. People living with undiagnosed and treated OSA can suffer from daytime drowsiness, higher risk of accidents as well as heart, kidney and metabolic health complications.
People with OSA often snore loudly, their breathing starts and stops during the night, and they may wake up several times. Not only does this cause tiredness, but it can also increase the risk of high blood pressure, stroke, heart disease and type 2 diabetes.
The new study now highlights the significant influence of plant-based diets on OSA risk, with particular emphasis on the protective role of diets rich in anti-inflammatory components and antioxidant nutrients and low in harmful dietary factors.
Dr Melaku says these new insights into how diet can influence OSA risk also have the potential to modulate other pathophysiological mechanisms, possibly affecting various other health conditions, from obesity to cardiovascular diseases.
"Furthermore, the distinct sex-specific patterns observed call for more personalised dietary interventions," he adds.
"Additional research with longitudinal data is crucial to substantiate these new findings, particularly focusing on how plant-based diets affect sleep apneoa risk, especially in the context of maintained body weight."
Participants were asked to explain everything they had eaten over the last 24 hours.
Researchers categorised this information according to whether people were eating a healthy plant-based diet (including whole grains, fruits, vegetables, nuts, legumes, tea and coffee) or a diet high in animal foods (including animal fat, dairy, eggs, fish or seafood and meat). They also looked at whether people were eating an unhealthy, plant-based diet (including refined grains, potatoes, sugar-sweetened drinks, sweets, desserts and salty foods).
"Obstructive sleep apnoea is a common condition and, despite the risks it brings, many people do not know they have the condition. We know that OSA can be treated and there are several things patients can do to help themselves. This includes eating a healthy diet, not smoking, trying to keep a healthy weight and being active."
The article, 'Plant-based and vegetarian diets are associated with reduced obstructive sleep apnea risk' (2024) by Yohannes Adama Melaku, Lijun Zhao, Robert Adams and Danny J Eckert has been published in the European Respiratory Society journal ERJ Open Research. DOI: 10.1183/23120541.00739-2023
Acknowledgements: Yohannes Melaku is supported by an NHMRC Investigator Grant (2009776). Danny J Eckert is supported by a NHMRC Leadership Fellowship (1196261).
