Researchers from Xiamen University in China analysed data from 175 countries between 2010 and 2021. They tracked how much vegetables, fruits, and red meat people consumed and compared it to rates of diabetes across different regions.
Their findings showed that not all “healthy” eating trends worked the same way in every country — or for every outcome.
According to the researchers, the common belief that more vegetables and fewer animal products always mean better health may be too simplistic.
The study found the effects varied depending on how much people ate, where they lived, and how developed their health systems were.
Diabetes burden rising globally
Diabetes now affects more than half a billion people worldwide. From 2010 to 2021, age-standardised incidence rates (ASIR) which adjust for ageing populations, rose by 20.8%.
Age-standardised mortality rates (ASMR) and disability-adjusted life years (ASDR), which reflect how many years of healthy life are lost, also increased globally.
Oceania recorded the highest disease burden across all three metrics, while East Asia’s burden was among the lowest. Sub-Saharan Africa ranked seventh in incidence but second in both death and disability, pointing to limited healthcare access.
More vegetables and fruits, less red meat not the answer?
The researchers found that global per capita consumption of vegetables and fruits had increased during the study period, while red meat consumption had declined.
Central Asia and East Asia saw the sharpest rise in vegetable intake, while Australasia had the biggest drop in red meat intake.
The Caribbean and Oceania led in fruit consumption, Southern Latin America topped the red meat charts, and Sub-Saharan Africa had the lowest consumption across all three food groups.
Vegetables: Not always safer in excess
Vegetables had a clear link to diabetes — though only up to a point. The study showed that when vegetable intake was below 80 kilocalories per person per day (roughly 320 grams), it helped lower death and disability rates from diabetes. But when intake rose above this level, the benefits were reversed.
The researchers stated that this was because eating large amounts of vegetables may crowd out other essential nutrients, like proteins and fats.
Additionally, certain cooking methods, like frying, can produce harmful compounds that may raise health risks.
In short, a moderate vegetable intake supports health, but overconsumption — especially without diet diversity — can backfire.
Fruits: A U-shaped curve
The effects of fruit consumption were also nuanced — its relationship with death and disability showed a U-shaped curve.
Moderate fruit intake (40 to 100 kcal per day, about 150 to 250 grams) was best for lowering diabetes-related disability, whereas too little or too much raised the risks.
The protective role of fruit comes from polyphenols and fibre, which help control blood sugar and reduce inflammation. However, excess fructose, especially from fruit juice or high-fructose fruits, may impair insulin sensitivity.
Regions like the Asia–Pacific and Western Europe showed the best outcomes, likely due to balanced diets and healthier overall lifestyles.
Red meat: Not all bad, in moderation
Red meat had the most surprising results. Higher red meat intake was associated with a lower risk of developing diabetes, but only to a certain extent.
The lowest death and disability rates occurred at around 200 kcal of red meat per person per day (roughly 100 grams of cooked lean beef). Beyond that, the risks started to climb again.
This challenges the black-and-white view that red meat is harmful. In fact, the researchers stated that lean red meat provides essential nutrients like iron and protein, which support metabolic health.
However, high consumption, especially of fatty or processed red meats, increases the risk of obesity and insulin resistance.
Lifestyle factors still matter more
Beyond food, the study looked at how lifestyle and economic development influenced diabetes. It found that higher socioeconomic development (measured by SDI) was linked to more cases of diabetes, but fewer deaths and less disability.
This suggested that wealthier countries diagnosed more cases but also managed them better.
At the same time, overweight and physical inactivity rates were found to be major drivers of diabetes burden, consistent with past research.
Furthermore, moderate alcohol use appeared to reduce diabetes deaths and disability, but heavy drinking raised risks.
The study also found that richer countries were doing better at preventing diabetes complications, even if more people were being diagnosed. But in low-income areas, late diagnosis and poor treatment options still led to high death rates.
Regional diets must be tailored
The study stressed the need for localised dietary recommendations. For instance, East Asia’s vegetable-heavy diets appeared protective, partly due to traditional cooking methods.
In contrast, Oceania, despite moderate fruit and vegetable intake, suffered from high diabetes rates due to processed food imports and genetic risk factors.
In regions with historically low red meat consumption, such as parts of Asia and Africa, modest increases could improve nutrition. But in Western countries where red meat consumption is already high, reductions may be needed.
As there is no one-size-fits-all solution, public health strategies must account for local eating habits, health systems, and even cooking styles.
Limitations and future indications
The researchers acknowledged some limitations. The FAO data equates food supply with consumption, which doesn’t account for waste.
The study also lacked gender-specific insights and didn’t include whole grains due to data limitations.
The researchers concluded: “When improving SDI levels, countries or regions should focus on increasing the number of fitness and exercise places, and actively encouraging people to participate in physical activities.
“For individuals, it is also important to increase physical activity, regularly exercise, and drink in moderation to reduce the risk of obesity.”
Source: Nutrients
“Longitudinal Association Between the Consumption of Vegetables, Fruits, and Red Meat and Diabetes Disease Burden: An Analysis of Multiple Global Datasets”
https://doi.org/10.3390/nu17071256
Authors: Manqiong Yuan, et al.
