Living to a ripe old age of 100 might seem like a pipe dream, but researchers studying the world’s elusive ‘Blue Zones’ believe cutting back on one specific food could help you live longer.

The term ‘Blue Zones’ is used to describe certain regions where people are said to live to 100 at rates ’10 times greater’ than those in the US. These zones include specific areas in Japan, Greece, California, Italy, Costa Rica and Singapore, each with their unique lifestyle habits.

Yet, you may be surprised to know that certain choices are notable across each of them, which reportedly includes keeping one thing to a minimum. Interestingly, this concerns fish, with just ‘three ounces, up to three times weekly’ suggested by Blue Zone researchers.

“In most Blue Zones, people ate some fish but less than you might think—up to three small servings a week,” they wrote in a past online blog. “… In the world’s blue zones, in most cases, the fish being eaten are small, relatively inexpensive fish such as sardines, anchovies, and cod—middle-of-the-food- -chain species that are not exposed to the high levels of mercury or other chemicals like PCBs that pollute our gourmet fish supply today.”

These researchers aren’t alone in their views. Dr Valter Longo, head of the Longevity Institute at the University of Southern California, also champions just ‘two or three’ servings per week as part of an adult’s ‘longevity diet,’ reports Devon Live.

“Eat mostly vegan, plus a little fish,” he wrote in a previous online blog. “Choose fish, crustaceans, and molluscs with a high omega-3, omega-6, and vitamin B12 content (salmon, anchovies, sardines, cod, sea bream, trout, clams, shrimp.

“Pay attention to the quality of the fish, choosing those with low levels of mercury.” As Dr Longo implies, fish packed with omega-3s—or ‘healthy fats’— significantly benefit our health.

These nutrients are key players in enhancing brain function and may help reduce risk factors associated with heart disease. But there’s a catch.

NHS guidance addresses these concerns, warning that oily fish ‘usually have higher levels of pollutants than other types of seafood’. One such pollutant is mercury, which can be harmful to our health.

Although the risks from eating fish are generally low, too much mercury can cause seizures, memory issues, numbness, and other symptoms. “We should eat at least one portion (around 140g when cooked) of oily fish a week,” the NHS states.

“Oily fish usually have higher levels of pollutants than other types of seafood. For this reason, there are maximum recommendations for the number of portions some groups should be eating each week.”

It adds: “[When pregnant] eating fish is good for your health and the development of your baby. However, pregnant and breastfeeding women should avoid some types of fish and limit the amount they eat of some others.

“This is because of the levels of mercury and pollutants that some fish can contain.” Beyond this, experts who study longevity hotspots recommend cutting down on dairy, red meat, and sugar.

These foods constitute a big part of the typical ‘Western diet’, which specialists have linked to several possible health risks, like cancer. Dan Buettner, a leading Blue Zone specialist, instead recommends eating more plant-based foods, beans and complex carbohydrates for better well-being.

Previously on TikTok, he said: “We know beyond a shadow of a doubt that people who live the longest, that we can actually record, were eating mostly complex carbohydrates. But the problem is the doughnuts and the cakes and the candies give carbohydrates a bad name.

“…You need fat, you also need protein, but you should be eating mostly complex carbohydrates if you actually want to live to 100.”