Chennai, Aug. 19 -- Highlights:
* Higher DASH diet adherence weakened the association between sedentary time and higher OSA risk
* The study included 797 adults with hypertension, 62.2% of whom had a //normal BMI
* The findings show an association, not proof that the DASH diet prevents sleep apnea
A study of 797 adults with hypertension found that higher adherence to the DASH diet weakened the association between prolonged sedentary time and increased risk of obstructive sleep apnea ( ref1 ).
Sitting for long periods has been linked to several health problems. A new study suggests that diet quality may influence the relationship between prolonged sitting and sleep apnea risk.
Researchers found that among adults with hypertension , longer daily sedentary time was associated with a greater likelihood of being in a higher obstructive sleep apnea (OSA) risk category. However, this link was weaker among people who followed the Dietary Approaches to Stop Hypertension (DASH) diet more closely.
Obstructive sleep apnea is a sleep disorder in which the upper airway repeatedly becomes blocked during sleep, causing breathing to stop and restart. It can lead to loud snoring , poor sleep quality, daytime tiredness, and reduced oxygen levels during sleep.
The study, published in Scientific Reports, included 797 adults aged 45 years and older with hypertension living in rural communities in China. Importantly, about 62.2% had a normal BMI, allowing researchers to examine the relationship beyond obesity, which is a major known risk factor for OSA.
Can Sitting Too Much Raise Sleep Apnea Risk?
The researchers found that sedentary time was independently associated with higher OSA risk. Participants reported a median of 3.5 hours of sedentary time per day , with those in the intermediate- and high-risk OSA groups reporting a median of about 4 hours per day.
The researchers suggest that prolonged sitting may affect OSA-related processes through increased abdominal fat, inflammation and changes in the body's stress response. These mechanisms may be particularly relevant in people with hypertension.
However, it is important to note that sedentary time was associated with OSA risk; the study does not prove that sitting causes sleep apnea.
How Did the DASH Diet Affect the Link Between Sitting and Sleep Apnea Risk?
The interesting finding came when researchers examined DASH diet adherence and sedentary time together . Participants were divided into four groups according to their DASH diet scores: td{ padding:10px; } th{ background: #187681; color:white; } DASH Adherence Score Q1 - Lowest <16 Q2 17-23 Q3 24-27 Q4 - Highest >27
The DASH diet emphasises foods such as fruits, vegetables and whole grains and is widely used as a dietary approach for blood pressure management. The researchers suggest that the DASH diet may influence sleep-related breathing through its effects on inflammation, oxidative stress and airway health. But there is an important distinction:
Following the DASH diet more closely was not, by itself, linked to a lower OSA risk. Instead, the diet appeared to weaken the link between prolonged sitting and OSA risk.
Higher DASH Adherence Was Linked to a Weaker Association
The researchers found that the relationship between longer sitting time and higher sleep apnea risk became weaker among people who followed the DASH diet more closely.
The link was strongest among participants with the lowest DASH diet scores and became progressively weaker as DASH adherence increased. This suggests that diet quality may influence how strongly prolonged sitting is associated with sleep apnea risk.
However, the study does not show that the DASH diet prevents sleep apnea or cancels out the effects of prolonged sitting.
Does the DASH Diet Reduce the Link Between Sitting and Sleep Apnea?
In simple terms, people who spent more time sitting tended to have a higher risk of sleep apnea, but this relationship was less pronounced among those who followed the DASH diet more closely.
This does not mean that eating a healthy diet makes prolonged sitting harmless. It simply suggests that diet and sedentary behaviour may work together in ways that affect sleep apnea risk.
Because the study was cross-sectional, researchers cannot say that the DASH diet itself caused the weaker association.
What Other Factors May Increase the Risk of Obstructive Sleep Apnea?
The researchers also found that some other factors were linked to a higher risk of sleep apnea.
Age was one of them. Participants aged 60 and above had a higher likelihood of being in a higher OSA-risk group than those aged 45-59 years.
Neck and waist size also mattered. A larger neck circumference and greater waist circumference were associated with higher OSA risk.
Interestingly, these associations were seen even though most participants had a normal BMI.
Most Participants Were Not Obese
Among the 797 participants:
* 62.2% had a normal BMI
* 24.0% were overweight
* 7.0% were obese
* 6.8% were underweight
This is worth noting because obesity is a well-known risk factor for obstructive sleep apnea. The study therefore provides some insight into other factors, such as sedentary behaviour and diet, that may be linked to OSA risk even in people who are not obese.
How Was Sleep Apnea Risk Measured?
The researchers did not diagnose obstructive sleep apnea using a sleep study. Instead, participants completed the STOP-BANG questionnaire, a screening tool used to classify people as:
* Low risk: score 0-2
* Intermediate risk: score 3-4
* High risk: score 5-8
Among the participants:
* 77.8% were classified as low risk
* 16.6% were at intermediate risk
* 5.6% were at high risk.
Therefore, the study should be interpreted as examining OSA risk, rather than proving that participants had obstructive sleep apnea.
Why Might the DASH Diet Help?
The study authors propose several possible explanations. The DASH diet is rich in fruits, vegetables and whole grains , and is recognised for its cardiometabolic and blood-pressure benefits. The researchers suggest that its anti-inflammatory and antioxidant effects could potentially influence pathways involved in sleep-disordered breathing.
Prolonged sitting may also contribute to abdominal fat, inflammation and changes in the body's stress response, which could affect sleep-related breathing.
This suggests that diet quality and sedentary behaviour may influence OSA risk together. However, this is only a possible explanation and was not directly tested in the study. But these mechanisms remain a hypothesis based on the current findings, rather than something the study directly tested.
Can the DASH Diet Offset the Effects of Prolonged Sitting?
No. This is perhaps the most important takeaway. The findings do not mean that people can sit for long hours and compensate simply by eating a healthy diet.
The study found that higher DASH adherence attenuated the association between sedentary time and OSA risk. It did not show that the diet eliminated the effects of sedentary behavior.
A healthier diet and less sedentary behaviour should therefore be viewed as complementary lifestyle strategies, not alternatives to each other.
What Did the Researchers Conclude?
The researchers concluded that higher DASH diet adherence may weaken the association between sedentary behaviour and elevated OSA risk among adults with hypertension, including those with predominantly normal body weight.
The finding may be relevant to people with hypertension because sleep apnea and high blood pressure can affect each other. However, more research is needed to determine whether improving diet or reducing sedentary time can actually lower OSA risk.
What Are the Study's Limitations?
There are several important limitations.
First, the study was cross-sectional. Participants' diet, sedentary behaviour and OSA risk were assessed at the same period, so the researchers cannot determine which came first.
Second, OSA risk was assessed using STOP-BANG rather than confirmed through diagnostic sleep testing.
Third, the study involved adults aged 45 years and older with hypertension living in rural communities in China. The findings may therefore not apply directly to younger adults, people without hypertension or other populations. The study sample came from seven communities in three counties along the China-Vietnam border and data were collected between March and June 2024.
The authors also acknowledge that the findings need further investigation before the DASH diet can be considered a specific strategy for reducing OSA risk.
The Bottom Line
A healthy diet may do more than support blood pressure. In this study of 797 adults with hypertension, longer sedentary time was associated with higher OSA risk, but that association became progressively weaker among participants with greater adherence to the DASH diet. However, the study does not prove that the DASH diet prevents sleep apnea or makes prolonged sitting safe.
For now, the practical message is simpler: eat a heart-healthy diet, stay physically active and avoid spending unnecessarily long periods sitting. The findings suggest that these lifestyle factors may work together in ways that deserve further study. medfaq Reference:
* Adherence to the DASH diet moderates the association between sedentary time and the risk of obstructive sleep apnea in a hypertensive rural Chinese population: a cross-sectional study - (https://www.nature.com/articles/s41598-026-64022-9)
Source-Medindia