Living a long and a healthy life is a cherished goal for many. Dan Buettner, who first discovered the blue zones, where people live the longest lives, recognised that one of the main factors of not just a long life, but a healthy one is the diet. There are documentaries too that have explored this topic. A Netflix documentary called Live to 100: Secrets of the Blue Zones, which revealed the lives of Centenarians, those who live 100 years or more. Studies reveal that a shared lifestyle patterns, and dietary habits is what benefits them.

What Are The Blue Zones?

"Blue Zones" include Okinawa, Japan; Ikaria, Greece; Sardinia, Italy; Nicoya Peninsula (Costa Rica); and Loma Linda, California.

It is true that centenarians can be found worldwide, but those in Blue Zones, share a common lifestyle habit. They prioritize in staying active, fostering close community ties, and maintaining a positive attitude. The diet, is something we all can learn and include in our lifestyle too.

"Blue Zones" are geographic areas with lower rates of chronic diseases and longer life expectancy. This is possible because of their diet, fasting, exercise, along with other factors. This term was first used by author Dan Buettner, who studied the areas of the world where people lived exceptionally long lives. He called them the "Blue zones", because when Buettner and his colleagues were searching for these areas, they drew it with a blue circles around them on the map.

The Centenarian Diet:

Legumes: It includes beans, peas, lentils. These are fiber-rich foods, that helps regulate cholesterol and blood sugar levels. It reduces the risk of chronic diseases such as heart disease and cancer. Their plant-based protein content makes them a nutritious and versatile addition to meals.

Olive Oils: A staple in Mediterranean diets, olive oil is prized for its healthy unsaturated fats, which support cholesterol balance. Rich in antioxidants like vitamin E and plant compounds, olive oil reduces inflammation and lowers the risk of chronic illnesses.

Nuts and Seeds: These are packed with unsaturated fats, vitamins, and minerals. The antioxidant content supports heart health and reduces inflammation. Centenarians' diets often include these nutrient-dense foods as snacks or meal components.

Tea: Its antioxidant-rich compounds boost immune, heart, and brain health. Regular tea consumption is linked to improved metabolic and digestive functions.

Seafood: Centenarians tend to eat less red meat and more seafood, particularly fatty fish rich in omega-3 fatty acids. These nutrients combat inflammation and enhance brain, heart, and immune health. The proximity of many Blue Zones to oceans influences this dietary preference.

Whole Wheat: Whole grains, including sourdough bread, are common in centenarian diets. Rich in fiber, B vitamins, and minerals, whole grains lower the risk of cardiovascular diseases and cancer. Sourdough fermentation enhances digestibility and supports stable blood sugar levels.

Sweet Potatoes: They are loaded with fiber, potassium, and vitamins A and C, which bolster immune and heart health. Regular consumption of sweet potatoes supports metabolic balance.

Turmeric: Its active compound, curcumin, is known for its anti-inflammatory properties. Turmeric promotes brain health and reduces the risk of chronic diseases, making it a valuable addition to meals.

It’s 3 pm. Are you feeling the familiar feeling of slow down with heavy eyelids, fading concentration and a sudden urge for coffee? While you may blame a busy schedule, long screen time or poor sleep for the afternoon slump, your nutrition levels may also play a role in how well you sustain your energy, experts said.

With increasing work stress and responsibilities, your body requires a steady supply of nutrients for energy production, brain support and normal body functioning. However, afternoon tiredness is not always a sign of nutrient deficiency. Sleep quality, stress, physical activity, hydration and even the natural dip in alertness that occurs during the day can influence energy levels.

Yet, nutrition can affect how well you sustain your energy through the day.

Could Your Lunch Be Making You Tired?

Speaking to HealthandMe, Meenakshi Aggarwal, Clinical Dietician, MAIINS, Marengo Asia Hospitals, Gurugram, said that a lunch built largely around refined carbohydrates or sugary foods, with little protein or fibre, may leave you feeling hungry again sooner.

“Choosing whole grains, pulses, vegetables, curd, eggs or other protein-rich foods can make a meal more balanced and support steadier energy,” she said.

The Nutrients That Matter

Before reaching for another cup of coffee, look at your plate. Iron deserves special attention. It is essential for hemoglobin formation and oxygen transport, as well as normal cellular energy metabolism. Research has found that people with iron deficiency can experience fatigue even without anemia.

“Iron is needed to make hemoglobin, the protein that carries oxygen around the blood. Fatigue, weakness, poor concentration, and reduced stamina are all symptoms of low iron levels. Lentils, beans, leafy greens, eggs and meat are iron-rich foods,” Shabana Parveen, Head, Nutrition & Dietetics, Artemis Hospitals, told HealthandMe.

Other nutrients, including vitamin B12, folate and magnesium, also have important roles in normal blood formation, nervous-system function and energy metabolism.

Vitamin B12 helps make red blood cells and keeps nerves healthy. Tiredness, weakness and concentration problems may be related to inadequate intake or poor absorption. Common sources include dairy products, eggs, fish and meat.

Magnesium participates in hundreds of processes in the body, including energy production and muscle function. Nuts, seeds, whole grains, legumes and leafy vegetables can help supply it.

When Fatigue Needs More Than A Diet Fix

The experts noted that fatigue alone does not prove a deficiency. Dehydration, irregular meals, too much caffeine, lack of sleep, stress, thyroid problems, anemia and other health conditions can also play a part, Parveen said.

Instead of reaching for another sugary snack or coffee, it is better to focus on balanced meals containing protein, whole grains, vegetables, fruits and healthy fats.

If tiredness is common, severe or persistent despite a healthy lifestyle, speak to a healthcare professional to identify the underlying cause.

A balanced lunch, adequate fluids and sufficient sleep may be more useful than simply pushing through the slump.

Why Nutrition Matters Beyond Energy

The importance of nutrition, however, goes beyond managing an afternoon energy slump.

Dr Sabine Kapasi, Global Health Strategist and a UN Advisor, told HealthandMe that preventive healthcare has traditionally centered on screening, exercise and early diagnosis.

Nutrition often receives less attention, despite being one of the strongest modifiable factors influencing long-term health.

“Nutrition matters because it affects several metabolic pathways at the same time. Weight, blood pressure, blood glucose and cholesterol are closely linked to diet and are major risk factors for cardiovascular disease, diabetes and other NCDs.”

Ever wondered why a food you have eaten comfortably for years suddenly starts causing bloating, abdominal discomfort or bowel changes? The food may not have changed — your gut may have.

Food intolerance can develop in adulthood as the gut microbiome, digestive enzymes, intestinal lining and gut-brain interactions change with age, illness, medications, diet, stress and other factors.

What Changes Inside The Gut?

“The intestine is a dynamic ecosystem. Its microbiome, immune system, intestinal lining and digestive enzymes are constantly changing and adapting to factors such as age, infections, antibiotics, medications, diet, stress and hormonal changes,” Dr. Amit Maydeo, Chairman, Institute of Gastrosciences, Sir HN Reliance Foundation Hospital, told HealthandMe.

Dr. Geeta Malkan-Billa, Director of Gastroenterology & Hepatology, Dr. L. H. Hiranandani Hospital, highlighted several changes that can affect food tolerance:

• Digestive enzymes: Lactase levels decline after childhood. For some, lactose intolerance can appear in their 20s–40s. Diamine oxidase, which helps break down histamine, can also decrease.
• Gut microbiome: Antibiotics, infections, illness and major diet changes can alter gut bacteria, changing how foods are fermented and potentially causing more gas or bloating.
• Past infections: Gastroenteritis can affect the gut lining, digestive enzymes and gut nerves for months, making certain foods harder to tolerate.
• Gut lining: NSAIDs, tobacco, heavy alcohol use and chronic stress can increase intestinal permeability and trigger low-grade immune activity.
• Gut movement: Ageing, surgery, diabetes, thyroid problems and GLP-1 medications can alter how quickly food moves through the gut, affecting fermentation and potentially contributing to bacterial overgrowth.

Why Does A Familiar Food Suddenly Cause Problems?

Dr Amit said that changes in gut bacteria can alter how carbohydrates and fibers are fermented, while a more sensitive gut lining can make previously tolerated foods feel uncomfortable.

A previous gut infection can also leave the gut more sensitive. After gastroenteritis, some people develop post-infectious IBS, which can make certain foods trigger symptoms.

Stress can further amplify these sensations through the gut-brain axis. As the nervous system becomes more sensitive, normal amounts of gas or intestinal distension may feel uncomfortable, Dr. Amit said.

It May Not Be Food Intolerance

Not every reaction to food is an intolerance. Some conditions can look similar but are actually different:

• Celiac disease: An autoimmune condition that can develop at any age, rather than simply an inability to digest gluten or wheat.
• Food allergy: True IgE-mediated food allergies can also develop during adulthood.

So, a new reaction to a familiar food should not automatically be labelled as food intolerance.

What Should You Do?

Before cutting gluten from your diet, get celiac serology testing, as going gluten-free beforehand can affect the results.

A two-week food and symptom diary can also help identify patterns. Note:

• What you ate
• How much you ate
• When symptoms appeared

The key is to remember that the food itself may not have suddenly become “bad” for you. Your gut’s ability to process and tolerate it may have changed.

Sometimes, however, a new food allergy or another gastrointestinal disorder may need to be ruled out.

When Should You See A Doctor?

Certain symptoms should not simply be blamed on food intolerance. See a doctor if you experience:

• Unexplained weight loss
• Blood in the stool
• Anaemia
• Symptoms that wake you at night
• Swelling
• Difficulty breathing

These symptoms need medical evaluation rather than simply eliminating foods from your diet.

Sorbitol is often seen as a healthier alternative to sugar. The sugar alcohol is widely used in sugar-free chewing gum, candies and other low-calorie foods, offering sweetness with fewer calories than regular sugar.

But new research suggests that sorbitol may not just pass through the digestive system as it was previously assumed.

Scientists have found that after reaching the liver, sorbitol may be converted into a compound related to fructose, where it could trigger metabolic changes associated with fatty liver disease.

How Sorbitol Interacts With The Body?

Researchers from Washington University in St. Louis used zebrafish models to analyse what happens to sorbitol after it enters the body.

They found that after eating a meal, sorbitol can be produced naturally in the intestine from the glucose. What happens next depends partly on the bacteria residing in the gut.

Certain bacteria, including Aeromonas strains that degrades sorbitol, can consume sorbitol and convert it into a harmless bacterial byproduct. This may act as a protective filter, preventing the compound from reaching the liver.

But when those bacteria are absent, more sorbitol may pass through to the liver. Researchers found sorbitol can be converted into a derivative of fructose.

The researchers describe sorbitol as being “one transformation away from fructose”, because of how closely the two compounds are connected through metabolism.

Also read: Should You Really Cut Out Rice And Roti To Lose Weight? Expert Explains The Truth About Carbs

Could Sorbitol Affect Liver Health?

The metabolism of fructose in the liver has been linked to steatotic liver disease, a condition in which excess fat accumulates in liver cells. The new findings suggest that sorbitol may have some of the same metabolic effects.

The researchers found that sorbitol could contribute to processes linked with liver fat accumulation when the gut's ability to break it down was impaired.

However, this does not mean that eating sugar-free gum or food containing sorbitol will automatically and mandatorily cause fatty liver disease.

The research was conducted in zebrafish, and the study is exploring a biological mechanism rather than demonstrating that ordinary dietary sorbitol causes liver disease in humans.

Also read: Bill Ackman’s Daughter Gets Experimental Treatment For Vision Loss: When Can Mitochondrial Transplants Help?

Gut Bacteria May Make A Difference

One of the more unexpected findings was the potential role of the gut microbiome in preventing this scenario. At relatively low levels, including amounts naturally obtained from fruit, researchers found that bacteria appeared capable of breaking down sorbitol.

Problems may surface when the amount of sorbitol becomes too high for these microbes to process efficiently. That could happen through consuming large quantities of products that contain sorbitol. High glucose intake may also increase the amount of sorbitol produced inside the intestine.

The researchers therefore suggest that how much sorbitol is consumed and the composition of an individual's gut bacteria could influence what happens to the compound and thus shape the risk of liver disease.

The study does not establish that sorbitol is harmful for humans even when consumed in moderate amounts. In fact, sorbitol occurs naturally in fruits such as stone fruits, and the researchers noted that relatively low amounts are generally handled effectively by gut bacteria.

The findings challenge the assumption that sugar substitutes are automatically metabolically healthy simply because they contain less sugar or fewer calories.