What Is Blue Light? How Does It Impact Sleep?

Updated Dec 14, 2024 | 10:45 PM IST

SummaryScreens of electronic devices such as smartphones, computers, tablets, and televisions emit blue light. But does it impact your natural sleep cycle and circadian rhythm?
Blue Light

Blue Light (Credit: Canva)

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?

Blue light is part of the visible light spectrum and is emitted by natural and artificial sources like the sun, fluorescent lights, LED lights, and digital screens. This wavelength is known for influencing our alertness, mood, and sleep patterns. During the day, blue light plays a role in regulating circadian rhythms, helping us stay alert and focused. However, exposure to it in the evening can have a detrimental effect on sleep quality.

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.

End of Article

This Is Much Coffee Should You Drink To Lower Stress, Study Reveals

Updated Mar 29, 2026 | 07:06 PM IST

SummaryA large new study suggests that about only two to four cups of coffee per day can reduce stress levels as well as lower the risks of developing anxiety and depression. Drinking more than four cups may start to increase stress and anxiety, likely because caffeine stimulates the nervous system and raises stress hormones
This Is Much Coffee Should You Drink To Lower Stress, Study Reveals

Credit: Canva

A large new study suggests that about only two to four cups of coffee per day can reduce stress levels as well as lower the risks of developing anxiety and depression.

Researchers from Fudan University in China found that moderate coffee intake is linked to lower stress levels, while both very low and very high consumption don’t offer the same benefit.

Drinking more than four cups may start to increase stress and anxiety, likely because caffeine stimulates the nervous system and raises stress hormones.

Scientists believe this works like a “J-shaped curve”: a little caffeine can improve mood, alertness, and resilience to stress, but too much can overstimulate the body and make stress worse. Supporting research also shows that high caffeine intake is linked to higher perceived stress and anxiety symptoms.

At the top end of the scale, drinking five cups or more each day was associated with a higher risk of mood disorders – so it seems it is possible to overdo the buzz.

"J-shaped associations were identified between coffee consumption and mental disorders, suggesting that a moderate intake of coffee might be beneficial for mental health," write the researchers in their published paper.

Caffeine Can Recover Memory Loss From Lack of Sleep

In this animal study, scientists at the National University of Singapore have found that sleep-deprived mice struggle to recognize other mice however, mice that were given caffeine for a week before being being sleep-deprived performed much better on tests and did not show the same memory loss.

Additionally, when caffeine was directly applied to brain tissue from sleep-deprived mice, it improved communication between brain cells in this region -- suggesting that caffeine doesn’t just mask tiredness but may also help repair disrupted brain activity.

NUS physiologist Lik-Wei Wong explained: "Sleep deprivation does not just make you tired. It selectively disrupts important memory circuits.

"We found that caffeine can reverse these disruptions at both the molecular and behavioral levels. Its ability to do so suggests that caffeine's benefits may extend beyond simply helping us stay awake."

"Our findings position the CA2 region as a critical hub linking sleep and social memory. This research enhances our understanding towards the biological mechanisms underlying sleep-related cognitive decline. This could inform future approaches to preserving cognitive performance," NSU neuroscientist Sreedharan Sajikumar added.

Based on these results, the study concluded that sleep deprivation increases signaling linked to adenosine, a chemical that promotes sleep but can also weaken memory circuits. But with moderate amounts of intake, caffeine appears to block this effect and help the brain maintain normal function

While the discovery offers a clearer understanding of how sleep, memory and caffeine are connected, the findings are based on mice and more research is needed to confirm if the same benefits apply to humans.

How Much Coffee Should You Consume?

Due to how much caffeine can actually affect one’s body, experts recommend 400 milligrams only per day. That is about four cups, it is also better to consult a doctor about this as caffeine sensitivity is different for people. Some people are more sensitive to caffeine than others.

How you react depends on your health, what medicines you take, and how fast your body processes things. Too much caffeine can cause problems, so it's important to pay attention to how you feel and not go overboard. Here is what happens to your body when you drink too much caffeine daily.

End of Article

Scientists Develop New Technique To Prevent AFib-Caused Strokes

Updated Mar 29, 2026 | 06:07 PM IST

SummaryAtrial fibrillation (AFib) is an irregular and often very rapid heart rhythm, also called an arrhythmia and can create blood clots in the heart, which can increase your risk of having a stroke by five times. Common symptoms include palpitations (the feeling that your heart is racing, chest pain, dizziness or feeling faint. However, a more severe symptom is a stroke
Scientists Develop New Technique To Prevent AFib-Caused Strokes

Credit: Canva

Atrial fibrillation (AFib) is an irregular and often very rapid heart rhythm, also called an arrhythmia and can create blood clots in the heart, which can increase your risk of having a stroke by five times.

When a person has AFib, the normal beating in the upper chambers of the heart (the two atria) is irregular and blood doesn't flow as well as it should from the atria to the lower chambers of the heart (the two ventricles).

Common symptoms include palpitations (the feeling that your heart is racing, pounding, fluttering or like you have missed heartbeats), chest pain, finding it harder to exercise, tiredness, shortness of breath, dizziness or feeling faint. However, a more severe symptom is a stroke.

Tucked inside the heart is a tiny pouch called the left atrial appendage. When the heart beats erratically, blood can pool and sit still in this pouch instead of flowing normally and still blood tends to clot. If one of those clots breaks free and travels to the brain, it can block blood flow and cause a stroke.

But researchers have now found new technique, in which a magnetically guided liquid is injected into the heart can harden and permanently seal the left atrial appendage from the inside. Early tests in rats and pigs suggest that this method could one day lower the risk of stroke in people with atrial fibrillation.

Based on this technique, researchers inject a magnetically responsive liquid, sometimes called a magnetofluid, directly into the left atrial appendage through a catheter.

Once inside the cavity, an external magnetic field helps guide and hold the fluid in place, so it fills the entire appendage, even against the force of circulating blood.

Within minutes, the liquid reacts with water in the blood and transforms into a soft "magnetogel" that seals off the cavity. Additionally, as the material begins as a liquid, it can adapt precisely to the highly irregular shape of each patient's left atrial appendage.

The death rate from AFib as the primary or a contributing cause of death has been rising for more than two decades.

Over 454,000 people with AFib are hospitalized in the US each year, out of which 158,000 die of the cause. It is estimated that 12.1 million people in the US will have AFib in the US will have AFib by 2050.

Who Is At Risk Of Having AFib?

Risk factors for AFib include:

  • Advancing age.
  • High blood pressure.
  • Obesity.
  • European ancestry.
  • Diabetes.
  • Heart failure.
  • Ischemic heart disease.
  • Hyperthyroidism.
  • Chronic kidney disease.
  • Moderate to heavy alcohol use.
  • Smoking.
  • Enlargement of the chambers on the left side of the heart.
In certain cases, AFib can be triggered by other things, such as alcohol, caffeine, smoking, recreational drugs, emotional stress and spicy food.

Treatment for AFib includes medications to control the heart's rhythm and rate, therapy to shock the heart back to a regular rhythm and procedures to block faulty heart signals.

A person with atrial fibrillation also may have a related heart rhythm disorder called atrial flutter. The treatments for AFib and atrial flutter are similar.

How To Improve Your Heart Health

Experts recommend following the below to reduce yor risk of stroke or developing AFib and maintaining heart health:

  • Don't smoke or use tobacco.
  • Aim for at least 150 minutes of moderate physical activity or 75 minutes of vigorous physical activity (or an equal combination of both) each week. Eat a heart-healthy diet.
  • Stay at a healthy weight.
  • Get quality sleep.
  • Manage stress levels
  • Get regular health screening tests.
  • Eat a fiber, nuts and fish-rich diet
  • Limit salt intake
  • Reduce saturated fat intake

End of Article

This Pill Is More Effective For Weight Loss Than Ozempic, Scientists Say

Updated Mar 29, 2026 | 05:02 PM IST

SummaryOrforglipron, a new daily pill, may be more effective than existing oral treatments for weight loss and blood sugar control than semaglutide, according to a recent clinical trial. Participants taking orforglipron lost around up to eight kilograms on average, compared to about five kilograms with semaglutide
This Pill Is More Effective For Weight Loss Than Ozempic, Scientists Say

Credit: Canva, Canada Insulin

Orforglipron, a new daily pill, may be more effective than existing oral treatments for weight loss and blood sugar control than semaglutide, according to a recent clinical trial.

Semaglutide belongs to a group of drugs known as GLP-1 medications, known to mimic a natural hormone that helps regulate appetite, slow digestion, and control blood sugar. The drug is commonly sold under the brand names Wegovy and Ozempic.

Despite being highly effective, semaglutide usually needs to be injected and requires refrigeration, which can make it inconvenient and harder to access for some patients. Additionally, the drug also carries a high price point.

However, in a 52-week trial involving people with Type 2 Diabetes, orforglipron was found to lower average blood sugar levels more than oral semaglutide and also led to greater weight loss.

Participants taking orforglipron lost around up to eight kilograms on average, compared to about five kilograms with semaglutide. Morever, orforglipron is a once-daily pill that does not require injections or cold storage.

But the study also found that orforglipron caused more side effects, particularly digestive issues like nausea and diarrhea. Yet scientists believe it may still be a better alternative to semaglutide as its easier and cheaper to produce than peptide-based drugs like semaglutide.

They also noticed that the drug absorbed more efficiently by the body and does not require strict timing around meals, unlike current oral versions of semaglutide.

READ MORE: Alkem Laboratories Launches Cheapest Semaglutide Injection In India

How Does Ozempic Function?

The first thing to remember here is that Ozempic is a brand-name medicine that contains semaglutide as its active ingredient. Semglutide is the synthetic version of GLP-1—a natural hormone produced in the intestines that regulates blood sugar, appetite, and digestion. Now, every time you eat, your body produces various hormones, including GLP-1. These are called Post nutrition hormones, and help you absorb the energy you just consumed.

GLP-1 travels to your pancreas, prompting it to produce insulin. It also travels to the hypothalamus in your brain, which gives you the feeling of being full or satiated. Ozempic imitates this hormone, thereby, silencing the food chatter in the brain. Interestingly, for some people this food chatter is really quiet ( people with low appetite) and for others it is an outbrurst, (people who generally binge eat.) So with Ozempic, silencing this self-talk in the brain, people tend to lose their appetite and eventually weight.

However, it is important to note that losing weight includes not just fat but muscle as well. Losing too much muscle can lead to reduced strength and a shorter life span. Notably, records show that most people who start taking them stop it at 12 weeks; therefore, it is important for some but not for others.

Does Ozempic Have Side Effects?

As reiterated by doctors and health care experts, Ozempic is a drug that is tasked to help diabetic patients manage their blood sugar levels and weight. However, recent research has shown its effectiveness in mitigating various addictions like alcohol and drugs by inhibiting hormones. But what people ignore are its side effects, which include:

  • Nausea is a frequent side effect, especially when starting Ozempic or increasing the dose, and vomiting may occur along with nausea.
  • Diarrhoea and abdominal discomfort also show up in people using Ozempic, but they generally resolve as your body adjusts.
  • Ozempic can reduce appetite but may also lead to unintended weight loss or reduced food intake, causing discomfort for some people.
  • There are certain less common, but serious side effects also, like Pancreatitis, or inflammation of the pancreas.
  • This drug may also cause severe kidney issues, particularly if dehydration occurs from side effects like vomiting or diarrhoea.

End of Article