Blue light emitted by devices like smartphones, computers, and televisions is becoming a major factor disrupting our sleep cycles. Research reveals that a significant number of Americans use electronic devices close to bedtime, contributing to poor sleep quality. Reducing exposure to blue light, particularly in the evening, is a simple yet effective way to help your body prepare for restful sleep.

What Is Blue Light?

How Does Blue Light Impact Circadian Rhythms?

Circadian rhythms are 24-hour cycles that control essential bodily functions, including sleep. Light is the primary factor that aligns these rhythms with day and night. Historically, exposure to sunlight during the day helped set our body clocks, signaling when to be awake and when to sleep. However, the widespread use of artificial lighting and electronic devices has introduced more light exposure after dark, disrupting these natural cycles.

Blue light, in particular, has the strongest impact on circadian rhythms. During daylight hours, blue light helps us feel alert by stimulating the brain, raising body temperature, and increasing heart rate. But in the evening, exposure to blue light can confuse the body’s internal clock, suppressing melatonin—the hormone responsible for making us feel sleepy. As a result, our brains may remain in “daytime mode,” preventing us from winding down for the night.

Health Consequences Of Disrupted Sleep

Persistent disruption of circadian rhythms can lead to a range of health issues, including metabolic disorders, poor mental health, and increased risk for conditions like depression and anxiety. Furthermore, the inability to sleep well at night affects cognitive performance, mood, and overall well-being. Chronic exposure to blue light in the evening may significantly contribute to these negative health outcomes.

Devices That Emit Blue Light

Many common devices in our daily lives emit blue light, including:

- Smartphones and tablets

- Computer monitors and laptops

- Televisions and e-readers

- LED and fluorescent lighting

- Video game consoles

How To Minimize Blue Light Exposure

To reduce the effects of blue light on your sleep, here are some practical strategies:

1. Turn off screens before bed: Try to avoid using electronic devices at least two to three hours before bedtime. Reducing screen time helps prevent blue light from interfering with melatonin production.

2. Adjust your lighting: Dim your home’s lights or switch to warmer-toned lighting in the evening. You can also use lamps with red or orange light, which are less likely to impact your circadian rhythms.

3. Night mode settings: Many smartphones and computers have a "night mode" feature that reduces blue light emission. Make use of these features to limit exposure in the hours leading up to bedtime.

4. Blue light-blocking glasses: Special glasses designed to filter out blue light may be helpful for some individuals. These glasses can block or reduce the melatonin-suppressing effects of blue light.

5. Apps for blue light reduction: There are several smartphone and computer apps available that reduce blue light emission, allowing you to use your devices before bed without disturbing your sleep.

6. Create a sleep-friendly environment: If you can’t control light sources in your bedroom, consider using an eye mask to block out ambient light and promote better sleep.

When Indian summers touch 48 degrees, it’s no longer just uncomfortably hot—it’s a serious public health challenge. Extreme heat affects everything from hydration levels in the body to digestion, the health of your skin, heart, and even mental well-being. Surviving (and staying healthy) through such brutal temperatures requires 360-degree body care, not just an extra glass of water or switching on the AC.

Dr P. Venkata Krishnan, Senior Consultant & Director—Internal Medicine, Narayana Hospital, Gurugram, in an interview with Health and Me, shared a complete and practical survival plan to help your body cope with the extreme Indian summer—inside and out.

Hydration: Go Beyond Plain Water

In intense heat conditions, your body loses water and electrolytes very quickly through sweat. Electrolytes help carry water to the blood and tissues. Hence, drinking only plain water in summer may not suffice. Try sipping water consistently at regular intervals instead of gulping large quantities at once. Electrolyte-rich fluids like coconut water, lemon water with a pinch of salt, or buttermilk are healthy, affordable options to soothe parched throats. Avoid excess caffeine, colas, and alcohol, as they increase dehydration; if you must indulge, have a glass of water before your coffee or alcoholic drink.

Pro tip: Check your urine colour—dark yellow is a warning sign of dehydration.

Eat Light, Cool, and Smart

Our digestive systems are also tired in extreme summers. Spicy, heavy, and oily foods generate more internal heat, which puts an additional burden on digestion. Opt for seasonal fruits like watermelon, muskmelon, papaya, and berries instead of chips and snacks.

To ease digestion, add items like curd, rice, cucumber, and bottle gourd to your meals. Avoid red meat and fried foods during peak summer days. Smaller, lighter meals are easier for the body to process in extreme heat. Find ways to increase hydration through fruits and vegetables in your food too, apart from water intake.

Protect Your Skin from Heat Damage

Heat doesn’t just tan your skin—it accelerates ageing, causes pigmentation, and triggers rashes. Incorporating a summer skincare regimen can help prevent damage to your skin.

1. Use a broad-spectrum sunscreen daily, even if you’re indoors.
2. Wear loose, breathable cotton or linen clothing.
3. Take cool (not ice-cold) showers to soothe overheated skin.
4. Seek medical advice for prickly heat, fungal infections, or sudden rashes—they thrive in sweaty conditions.

Mind Your Heart and Blood Pressure

Extreme temperatures put additional stress on the cardiovascular system, especially in people with hypertension, diabetes, or heart conditions. There are just a few things to bear in mind. When the temperature outside sizzles, avoid stepping outdoors for prolonged periods, especially between 12 pm and 4 pm, when the sun beats down mercilessly.

Take all prescribed medications exactly as advised—don’t skip doses even if you experience heat-induced nausea. If you feel dizzy or experience palpitations or severe fatigue, consult your doctor as soon as possible. Heat exhaustion can silently progress to heatstroke, which is a medical emergency.

Smart Cooling at Home and Work

Air conditioning is helpful, but overexposure can lead to dry skin, headaches, and respiratory discomfort. However, since the emphasis is more on cooler environments in summer, there are a few ways to avoid overexposure to AC.

Once every two or three hours, step away from your desk for a few minutes. Walk or stand, and sip some water. Open windows, if possible, to avoid thermal shock. Set AC temperatures between 24 and 26 degrees, despite the urge to cool the surroundings further. Use fans and cross-ventilation whenever possible, relying a little less on air conditioning in the process. Never move directly from extreme heat into freezing AC environments, or vice versa, as it can impact your body suddenly.

Sleep & Mental Well-being Do Matter

Poor sleep due to heat can increase irritability, anxiety, and fatigue. Include some calming activity before bedtime. Put away screens, as they radiate heat too. Some tips to help you sleep better:

1. A lukewarm shower before bed.
2. Well-ventilated bedrooms.
3. No heavy dinners or eating late at night; ideally, finish dinner before 9 pm, leaving a gap of a couple of hours afterwards before going to sleep.
4. Mindful slow breathing or short meditation helps control heat-related restlessness.

Special Care for Vulnerable Groups

Children, elderly individuals, pregnant women, and outdoor workers are at higher risk of heat-related health concerns. They should particularly ensure that they hydrate more frequently.

1. Watch for signs like dry mouth, lethargy, confusion, or reduced urination. Seek a doctor’s advice if needed.
2. Include cooling foods to prevent dehydration and encourage lighter, frequent meals instead of full, heavy meals.
3. Never leave children or pets inside parked vehicles or in spaces without ventilation—even for a few minutes.

A holistic approach covering hydration, nutrition, skincare, heart health, and mental well-being can help your body adapt and stay resilient. Extreme heat is not “just a bad summer." Treat it seriously, listen to your body, and make smart daily choices, because protecting yourself from the heat today prevents long-term health problems tomorrow.

Cancer is one of the most dreaded diseases. It is characterised by a malignant tumor that obstructs the normal functioning of organs. According to a recent analysis from the World Health Organisation (WHO), more than a third of cancer cases in the world are preventable. Cervical, stomach, and lung cancers make up half of the cases. This implies that millions of such deadly cases in the world can be prevented with behavioural changes, timely medical intervention, reduced occupational risks, and an ability to tackle environmental pollutants. It turns out that most preventable cancers can be avoided by making two simple lifestyle changes.

Preventable cancers in the world

Researchers say that addressing preventable causes represents one of the most powerful opportunities to reduce the global cancer burden. The analysis also noted that, in 2022, there were approximately 19 million new cases of cancer, and 38 per cent were related to 30 modifiable risk factors. The most common modifiable risk factors are:

1. High BMI
2. Smoking
3. Insufficient physical activity
4. Alcohol intake
5. Smokeless tobacco
6. Air pollution
7. Exposure to infectious agents
8. Suboptimal breastfeeding
9. Occupational exposures

What are the preventable risk factors for cancer?

The most common preventable risk factor, however, was smoking tobacco. It is associated with 15 per cent of all cancer cases in a year. In men, the risk was significantly higher. Smoking contributed to 23 per cent of the new cancer cases globally in men that year. However, smoking alone was not the only cause; air pollution, depending upon the region, played a huge role. In East Asia itself, 15 per cent of lung cancer cases in women were attributed to air pollution. In Western Asia and Northern Africa, 20 per cent of lung cancer cases in men were due to air pollution.

After smoking tobacco, the next key lifestyle risk factor was drinking alcohol. It accounted for 3.2 per cent of all cancer cases—approximately 7 lakh. As per researchers’ estimates, drinking alcohol and smoking tobacco account for about 48 per cent of all preventable cancer cases. Infections, however, were associated with 10 per cent of new cancer cases. Among women, the largest share of these cases was attributed to high-risk human papillomavirus (HPV), which contributes to cervical cancer cases. However, with the HPV vaccine being more accessible, cervical cancer cases have reduced.

Can smoking give you stomach cancer?

Stomach cancer cases are higher among men and are mostly associated with inadequate sanitation, smoking, infections, and poor access to clean water. A first-of-its-kind analysis, this study helps show how much cancer risk comes from preventable causes. By examining these patterns, countries can be alerted to work towards preventing cancers in the first place by taking appropriate steps.

Researchers also mentioned in their paper that 4 in 10 cancer cases in the world in 2022 could have been prevented by eliminating the risk factors considered in the study. The study was published in the Nature Medicine journal.

Sleep is a very crucial part of one's life, and it can affect one's life as a whole. The sleep cycle and duration can determine a lot about one's physical and emotional well-being. Even biological aging is also immensely affected by the right amount of sleep, according to a recent study. The aforementioned research was published in Nature, and as per it, getting too little or too much sleep may speed aging in the brain and other body organs as well.

There were several studies that have been done on the same topic, and many of them concluded that getting less sleep can cause the speeding of one's biological age. Although this new study has come up with a new finding, and it went further than the previous studies on the same topic, the research shows that getting more sleep can also lead you to the same situation, and your biological aging speed can go higher due to it.

The lead study author, Junhao Wen, PhD, assistant professor of radiological sciences at Columbia University, said, “Sleep is fundamental for healthy aging and longevity. More importantly, it is potentially modifiable." He added, “In this study, we measure biological aging clocks across organs to link these clocks with sleep duration.”

The biological age is inherently different from chronological age, which is measured by the number of years one is alive, but on the other hand, biological age measures how quickly your cells and tissues are aging. Researcher Junhao Wen has done his research with different aging clocks, and these clocks are scientific, computational models that estimate a person’s biological age and how they are aging faster or slower than their chronological age.

Wen and his colleagues assessed the relationship between a person’s self-reported sleep duration and their biological age, using 23 aging clocks across 17 organs. The research defined too little sleep as less than 6 hours and too much sleep as more than 8 hours. The study concludes that, in general, people who slept too little or too much showed signs of faster biological aging than those who reported sleeping between 6.4 and 7.8 hours each day.

The same study also sheds light on the relationship between sleep and chronic diseases. The research suggests that a connection exists beyond brain influence. Notably, less sleep causes disorders like depression and anxiety disorders. Other possible conditions related to it are obesity, type 2 diabetes, hypertension, ischemic heart disease, and heart arrhythmias. On the other hand, longer sleep is associated with depression and illness.