This discovery comes at a time when the world is witnessing a steady rise in the health burden caused by heart disease, which has become the leading cause of death worldwide, surpassing diseases such as cancer and chronic respiratory diseases in many regions.
What is even more alarming is the noticeable shift in the category of those affected by these risks towards younger age groups, which makes it imperative to examine modifiable lifestyle factors, especially dietary habits.
Fast food, with its well-known characteristics of being high in calories, saturated fat, and salt, and lacking in beneficial nutrients such as fiber and vitamins, is a major contributor to weight gain, high blood pressure, and cholesterol imbalances. However, the current study adds a new and alarming dimension, linking these meals to an elevated Dietary Inflammatory Index (DII) in the body.
Chronic low-grade inflammation is a cornerstone of heart disease development, contributing to atherosclerosis and blood clot formation. While healthy diets (such as the Mediterranean diet rich in fish and vegetables) reduce this inflammation, the highly processed Western diet, exemplified by fast food, significantly increases its biomarkers.
The study relied on an analysis of data from more than 8,500 participants in the U.S. National Health and Nutrition Examination Survey (NHANES) between 2009 and 2018. The results revealed a number of alarming indicators:
• Clear link to elevated inflammation levels:
After adjusting for other contributing factors, consuming fast food six or more times a week was found to be associated with a significantly higher energy-adjusted dietary inflammatory index compared to those who consumed it once a week or less. This effect was most pronounced in people aged 60 to 80.
• Decline in cardiovascular and metabolic health indicators:
Excessive consumption of fast food has been linked to:
Low levels of good cholesterol (HDL).
Increased triglycerides.
Elevated fasting blood sugar and insulin levels, and increased insulin resistance.
• Gender difference in effect:
The results showed that the negative metabolic effects of fast food were more severe in women compared to men, indicating greater sensitivity in females to this dietary pattern.
• Relationship to mortality:
While no direct and strong association was found between fast food consumption and increased mortality in this sample, a higher dietary inflammation index alone was associated with an increased overall mortality rate, with a trend suggesting a possible increase in cardiovascular disease deaths. This reinforces the role of inflammation as a key factor in increasing health risks.
Because the study is of the observational cross-sectional type, it does not prove a direct causal relationship, but it provides strong evidence that warrants preventive interventions at the public policy level, such as:
Raising awareness of the dangers of excessive consumption of fast food.
Restaurants and delivery platforms are required to display clear nutritional labels about the content of meals in terms of saturated fat, salt and sugars.
Setting health standards for meals served in institutions such as hospitals, schools, universities and workplaces.
Supporting the provision of healthy and affordable food alternatives to reduce reliance on unhealthy options.
This study confirms that frequent consumption of fast food is not just an unhealthy dietary habit associated with obesity, but a direct driver of increased systemic inflammation in the body, which in turn represents the royal road to increased risks of heart and metabolic diseases.
The results indicate that reducing reliance on these meals and shifting towards anti-inflammatory dietary patterns could be key pillars in strategies to improve public health at the community level.
