In a discovery that may make some rethink their morning ritual, new research has found a potential link between drinking instant coffee and a significantly higher risk of developing age-related macular degeneration (AMD), a leading cause of blindness among older adults.

The findings, published in the journal Food Science & Nutrition, are based on data from more than 500,000 individuals in the UK Biobank.

Researchers observed that participants who regularly consumed instant coffee and carried a specific genetic predisposition were up to seven times more likely to develop dry AMD—the more common and currently untreatable form of the disease.

What is Dry AMD?

Dry AMD gradually damages the macula, the central portion of the retina responsible for sharp, detailed vision. Over time, it can lead to blurred sight, difficulty in reading, and eventually, irreversible vision loss. While age and genetics are the most recognized risk factors, researchers have long suspected that lifestyle and dietary choices also play a role in the progression of this disease.

Coffee and Its Complicated Role in Health

Coffee is one of the most consumed beverages globally and is often touted for its health benefits. Rich in antioxidants and polyphenols, it has been associated with a lower risk of conditions like Parkinson’s disease, type 2 diabetes, and even some cancers. However, not all coffee is created equal.

This new study adds a surprising twist—instant coffee may not offer the same protective benefits as brewed coffee and may, in fact, be linked with negative outcomes for eye health, especially in people with certain genetic backgrounds.

Genetic Factors and Coffee Preference

The researchers behind the study believe that the preference for instant coffee might itself be influenced by genetic factors. Their analysis suggests there could be a shared biological mechanism between genes that influence coffee consumption habits and those that increase the risk of AMD.

This doesn’t necessarily mean that instant coffee directly causes AMD. However, the correlation hints at a complex interaction between genetics, dietary choices, and disease risk that warrants further investigation.

Dry AMD is a growing public health concern, especially in industrialized nations where people are living longer. It affects millions of people globally and can severely reduce quality of life. Given its slow but progressive nature, early detection and lifestyle management are key to preserving vision.

The new findings could pave the way for more personalized lifestyle advice based on genetic risk.

For example, individuals identified with a higher genetic susceptibility to AMD might benefit from moderating their intake of instant coffee or switching to brewed varieties.

More Research Is Required

While the study’s findings are compelling, researchers caution that more work is needed to establish a causal link. Future studies are expected to examine whether instant coffee itself contributes to retinal degeneration, or whether other factors—such as additives, processing methods, or associated lifestyle habits—may be at play.

Long-term population studies and deeper exploration into the metabolic pathways involved will be critical to understanding the full picture. Until then, the study offers a timely reminder that even seemingly minor lifestyle choices, like the type of coffee you drink, could have long-term implications for health—especially when genetics are involved.

For now, experts recommend a balanced approach that includes regular eye check-ups, a nutrient-rich diet, and avoiding smoking—alongside being mindful of what’s in your coffee cup.

You’ve seen it on your Instagram feed, heard your gym buddy rave about it, maybe even tried it yourself to drop those stubborn pounds. Cutting carbs, loading up on fats, watching the scale tip in your favor—it all sounds like magic, right? And within weeks your jeans fit better. The ketogenic diet, once a niche medical treatment, has exploded into a mainstream weight-loss trend. From celebrities to fitness enthusiasts, people across the globe have adopted keto for its promise of quick weight loss and better energy. But beneath the headlines and transformation posts lies a more complex reality—especially when it comes to your internal health.

But here’s the thing, behind the dramatic before-and-after photos and bulletproof coffee obsession, there’s a whole lot more happening inside your body than just fat burning. What does this ultra-low-carb lifestyle really mean for your gut, heart, brain, skin, liver, and kidneys? Is it a metabolic makeover—or are there trade-offs we’re not talking about enough?

We asked top experts to weigh in, and their answers may surprise you because while keto might help you slim down in the short run, your organs could be telling a very different story in the long haul.

The keto diet fundamentally shifts how your body generates energy. "By cutting carbs drastically, the body enters ketosis, burning fat for fuel instead of glucose," says Dietician Drishya Ale. Initially, the weight loss is mostly water due to lowered insulin and glycogen stores. But this carb-cut also means cutting out most fiber-rich foods—fruits, legumes, and whole grains.

"That can lead to constipation and disrupt your gut microbiota," she says. Add to that a spike in fat intake—often difficult to digest for some—and you get bloating or discomfort. While some people eventually report more energy and reduced appetite, others struggle with fatigue and vitamin deficiencies.

Drishya’s says, "Not all keto is the same. A clean keto approach with whole foods is a far cry from one loaded with processed meats and saturated fats."

Heart

Dr. Neerav Bansal, Cardio Thoracic Vascular Surgeon, "Keto may improve some heart markers in the short term—like lowering insulin, blood sugar, and triglycerides," says Dr. Neerav Bansal. But it’s not a one-size-fits-all fix.

Some people may experience a rise in LDL (bad cholesterol), especially if their keto is heavy in saturated fats from red meat and full-fat dairy. "This is particularly risky for those with a personal or family history of heart disease," he cautions.

In the long term, the heart health effects depend on the quality of fats consumed. Unsaturated fats from avocados, nuts, and olive oil can support heart health, while overloading on processed food and saturated fat can do damage.

Dr. Bansal emphasizes moderation, regular monitoring of cholesterol, and a personalized approach tailored to individual health profiles.

Brain

"The brain loves ketones, ketones, produced during ketosis, may be a more efficient energy source for the brain than glucose. For some, this translates to better focus, memory, and mental clarity," explains Dr. Mahesh Gour, Memory Coach, Cognitive Expert

There's research suggesting keto reduces brain inflammation and oxidative stress, which are linked to cognitive decline. That’s why keto is being explored for conditions like epilepsy, Alzheimer’s, and Parkinson’s.

But Dr. Gour warns, “If not properly managed, long-term keto can cause nutrient shortages and even affect mood or serotonin levels.” In other words, the same diet that sharpens your focus could also dull it, if not followed wisely.

Skin and Hair

However, it’s not all glow. "In early phases, some experience keto rash, and temporary hair loss due to stress on hair follicles," she notes. Over time, poor nutrition—especially lacking vitamins A, C, E, biotin, and zinc—can lead to dull skin and thinning hair.

Follow a nutrient-rich keto plan and supplement when necessary. Also, avoid overdoing saturated fats, which can clog pores and trigger breakouts in some.

Liver

The liver is central to the keto diet. "When carbs are restricted, the liver shifts gears and converts fat into ketones," explains Dr. Dhruv Kant Mishra, Gastroenterologist. For people with fatty liver disease or prediabetes, this can actually be beneficial—improving insulin sensitivity and reducing liver fat but not everyone wins.

"Without supervision, a high-fat diet can overwork the liver, raise enzyme levels, or cause inflammation," Dr. Mishra cautions. The quality of fats matters, as does duration and individual liver health.

His advice is simple, don’t do keto solo. Especially for those with any liver conditions, professional monitoring is essential.

Kidneys

Keto affects kidney function more than most realize. "Lower insulin leads to sodium loss, which can cause dehydration and mineral imbalances," says Dr. P. N. Gupta, Nephrologist. This is usually manageable with more water and electrolytes—but not always.

High animal protein intake—a hallmark of some keto diets—can increase acid buildup and strain the kidneys. "For people with underlying kidney issues, this can be dangerous. Even healthy individuals may face higher kidney stone risk due to changes in urine pH and calcium levels."

Dr. Gupta also flags the risk of gallstones and nutrient deficiencies with long-term keto. His recommendation? Anyone with kidney, liver, or metabolic conditions should only try keto under medical supervision.

The ketogenic diet can yield real health benefits—but it's not a universal fix. Depending on how it's implemented and who’s following it, keto can either help or harm.

Every expert agrees on this: choose clean, whole-food fats, stay monitored, supplement as needed, and work with a qualified healthcare provider.

Done right, keto might improve your metabolism, heart health, cognitive function, and skin. Done wrong, it could damage vital organs and disrupt body systems in ways that aren’t immediately obvious.

So before you jump in, pause and understand your body, talk to your doctor, and remember—no diet should be a gamble with your long-term health.

Coffee is an essential part of our day, whether we begin our day with it or have it at small intervals other times. However, have you ever wondered how long does it take for coffee to get absorbed into our body? And how long does it take to get absorbed into our bodies?

Caffeine gets into your system quite fast, usually within 45 minutes of drinking it. The highest levels of caffeine are typically seen between 15 minutes and up to two hours later, depending on the individual and if you drink it with food.

For most healthy people, about half of the caffeine you consume is cleared from your body in roughly five hours. This is known as its "half-life."

Many things can affect how quickly your body processes caffeine, including your age, sex, whether you're pregnant, your weight, and if you smoke. Some people are more sensitive to caffeine because of differences in the enzymes in their liver that break it down.

What Happens When You Have Caffeine In Your System?

The Cleveland Clinic explains that caffeine can make you feel more awake, alert, and focused, and it can even improve your mood. However, too much caffeine can cause negative effects like higher blood pressure, an upset stomach, and jitters. In very rare situations, a caffeine overdose can even be life-threatening.

Caffeine's Impact on Your Brain

As a stimulant, caffeine makes your central nervous system more active, which controls everything from thinking to moving. It boosts wakefulness by blocking a brain chemical that causes tiredness, making you feel more alert. It can also improve focus and mood by activating other brain chemicals. However, too much caffeine can lead to anxiety, jitters, and trouble sleeping, as it over-excites your nervous system.

Caffeine and Your Heart

While moderate coffee drinking may benefit heart health by potentially lowering blood pressure and cholesterol, caffeine can also have negative effects. It can cause mild increases in blood pressure and heart rate, which might be problematic for those with existing heart conditions. Higher doses of caffeine can lead to heart palpitations, making your heart feel like it's racing or fluttering, though these are usually not dangerous.

Caffeine and Your Digestive System

Too much caffeine can cause digestive issues. It has a laxative effect by stimulating the gut and speeding up food movement, which can lead to diarrhea in sensitive individuals. Caffeine can also increase stomach acid production and relax a muscle that prevents acid reflux, resulting in uncomfortable heartburn. Coffee's natural acids can intensify these digestive problems.

Caffeine's Effects on Other Body Systems

Caffeine acts as a diuretic, meaning it helps your body eliminate excess fluid, which might lead to more frequent urination. While unlikely to cause dehydration on its own, it's crucial to also drink plenty of water. Furthermore, caffeine can reduce your body's ability to absorb calcium, potentially affecting bone strength, especially with high consumption or insufficient dietary calcium.

How Much Caffeine Is Too Much?

Drinking too much caffeine can cause unwanted effects like feeling anxious, having a fast heartbeat, feeling restless, and having trouble sleeping.

The US Federation and Drug Administration generally recommended that adults keep their caffeine intake under 400 milligrams per day to avoid taking too much. People who are sensitive to caffeine might want to limit themselves to just one or two cups of caffeinated coffee or tea per day to prevent side effects like jitters and sleep problems.

Because caffeine stays in your system for a while, it's a good idea to avoid caffeinated drinks, like coffee, before going to bed.

How Long Before Sleeping Can You Have Caffeine?

A 2013 study published in the Journal of Clinical Sleep Medicine suggested that one should avoid drinking coffee at least 6 hours before sleeping. Researchers found this by giving participants 400 mg of caffeine at 0, 3, or 6 hours before their usual bedtime, comparing it to a placebo.

The findings showed that caffeine significantly disturbed sleep at all three time points, reducing total sleep time. This suggests that even caffeine consumed six hours before bed can negatively impact sleep, supporting the recommendation to avoid significant caffeine use for at least six hours before bedtime.

Relying solely on sunshine to meet your Vitamin D needs may not be enough—especially all year round. A recent study published in Nutrition & Metabolism, titled Vitamin D—is the sun enough for us?, has found that while sunlight helps your body produce Vitamin D, it may fall short in helping you maintain healthy levels over time. The research suggests that many people—particularly those with darker skin tones, higher body fat, or limited sun exposure—may still need supplements to meet their daily requirements.

How Much Sun Is Enough?

To get enough Vitamin D from sunlight, experts typically suggest spending about 5 to 30 minutes outdoors, a few times a week, between 10:30 am and 4 pm. But the study found that this general advice doesn’t work for everyone. Factors like where you live, your skin colour, time of year, and even air pollution can affect how much Vitamin D your body makes from UVB rays.

For instance, people living in northern latitudes or in places with long winters may not get enough sunshine for several months. And if you spend most of your day indoors, cover your skin, or live in areas with high pollution, your Vitamin D production can be even more limited.

Can Summer Sun Last You Through Winter?

Not really. The researchers explain that even if you spend more time outdoors in the summer and your body makes extra Vitamin D, it doesn’t stay in your system indefinitely. Vitamin D is stored in your fat and muscle tissues, but those reserves tend to run low by the time winter hits. This means you may still become deficient in the colder months unless you get enough from food or supplements.

Skin Tone and Body Fat Matter

Your skin color plays a major role in how efficiently you make Vitamin D. People with darker skin have more melanin, which acts like a natural sunscreen and slows down Vitamin D production. As a result, they often need longer sun exposure to make the same amount of Vitamin D as someone with lighter skin.

Body fat is another important factor. Vitamin D is fat-soluble, meaning it gets stored in fat tissue. In people with higher body fat, more Vitamin D can get trapped in fat cells and may not be easily released into the bloodstream. This can lower your blood levels even if your body has technically made enough.

On the flip side, muscle mass can actually help release stored Vitamin D more efficiently, suggesting that regular physical activity may improve your Vitamin D levels.

What About Sunscreen?

There’s a common concern that sunscreen blocks Vitamin D production. The study addressed this too, noting that while sunscreen can reduce UVB absorption, about 15% of UV rays still reach the skin. That means you’ll still make some Vitamin D even with sunscreen on. Dermatologists continue to recommend sunscreen to protect against skin cancer, and they suggest getting your Vitamin D through diet or supplements instead of skipping sun protection.

Other Sources of Vitamin D

You don’t have to rely only on sunlight. Some great sources of Vitamin D include:

Fatty fish (like salmon, tuna, and mackerel)

• Fortified foods (milk, orange juice, plant-based milks)
• Egg yolks and mushrooms
• Supplements
• Vitamin D supplements are especially helpful during winter or if you’re at risk of deficiency.

D2 vs. D3: Which One Should You Take?

The study found that Vitamin D3 is more effective than D2. D3 stays in your body longer and raises your blood levels more consistently. D2 breaks down faster and doesn’t maintain levels as well, making D3 the preferred option for most people.

How to Know If You’re Deficient

The only way to know for sure is through a blood test that measures your serum 25-hydroxyvitamin D (25(OH)D) levels. Experts recommend aiming for levels above 30 ng/mL for good health.

If your levels are low, your doctor might suggest taking daily supplements—anywhere from 600 IU to 2,000 IU, or even more if you’re obese or severely deficient.