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.

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Hidden In Plain Sight: Why Many Middle-aged Indian Women May Have Fatty Liver Disease And Not Know It

Updated May 10, 2026 | 10:00 PM IST

Summary Women may have a higher risk of life secondary to NAFLD when compared with men of the same age group. Conditions like age of menarche (first menstrual period), menopause status, alteration in reproductive hormones, and sarcopenia (muscle loss) may affect the development of NAFLD.
Hidden In Plain Sight: Why Many Middle-aged Indian Women May Have Fatty Liver Disease And Not Know It

Credit: Canva

Non-alcoholic fatty liver disease (NAFLD) is the commonest non-communicable disease in Indian women, with a prevalence rate of 35%. Globally, 30% of the population is suffering from NAFLD, and this projection is expected to progress to 56%, in a similar range to diabetes and obesity.

In India, the high rate of NAFLD is driven by the adoption of a westernized lifestyle, associated comorbidities like diabetes, obesity & hypertension. Fatty liver is known to progress to cirrhosis (end-stage liver disease) or liver cancer (hepatocellular cancer) if left untreated, which affects the survival rates and implicates a poor prognosis.

Unfortunately, it’s a silent disease and often presents at an advanced stage, leading to serious complications.

Why Women Face Different Risks Than Men

Women tend to have different outcomes with fatty liver disease when compared to men. Women may have a higher risk of life secondary to NAFLD when compared with men of the same age group. Conditions like age of menarche (first menstrual period), menopause status, alteration in reproductive hormones, and sarcopenia (muscle loss) may affect the development of NAFLD. Hormonal issues like oestrogen deficiency and Polycystic Ovarian Disease (PCOD) increase the risk of developing NAFLD. Women with type 2 diabetes, obesity, and larger waist circumference (metabolic syndrome) are more prone to NAFLD.

Besides physiological and hormonal factors, there are social and cultural factors like limited autonomy for women, hierarchy based on earning potential, and poor literacy levels (especially in rural regions), which may create health neglect or gender bias towards women’s health, and conditions like NAFLD can go neglected or ignored.

Fatty Liver Disease Is Preventable and Reversible

The urban populace has its own share of modern problems like alcohol, smoking, and a sedentary lifestyle. Fatty liver is totally preventable and reversible if diagnosed at an early stage with simple lifestyle modifications. Studies show that a diet high in protein and low in carbohydrates, or a diet with fruits and vegetables and whole grains combined with exercise for 30 minutes a day and 5 days a week, can significantly reverse fatty liver and liver cell inflammation.

There are no gender-based guidelines to treat or prevent this problem. In general, reducing the cardiovascular and metabolic risk remains the cornerstone to treat NAFLD in both men and women.

Weight Loss Can Significantly Improve Liver Health

Research shows that up to 10% weight loss can reduce liver scarring and inflammation, whereas between 5-10% weight loss can reduce liver fat significantly.

There is some evidence that suggests black coffee (without sugar), Vitamin E, and Omega-3 fatty acids help prevent and reverse NAFLD. Specific and early consultation with a specialist (e.g. cardiologist, endocrinologist, or a gynecologist) can control the morbidity and mortality around the problem. Fatty liver has reached an epidemic level problem and therefore needs mass screening & awareness programs.

Early Diagnosis Is the Key

Early diagnosis is key and can be achieved by simple USG of the liver or Fibro scan combined with simple blood tests, liver LFT’s (liver function tests). Unfortunately, there’s no pill to replace exercise or a healthy lifestyle; otherwise, it would have been a blockbuster medicine.

However, the good news is this deadly and silent disease has a simple and inexpensive solution: a healthy diet and plenty of exercise, which is accessible to all. There is also an urgent need to increase awareness in women on NAFLD and ways to combat it, so they can get access to life-saving treatment at the earliest.

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First Oral Drug For Thalassemia: A Breakthrough—But Are We Diagnosing In Time?

Updated May 10, 2026 | 03:00 PM IST

SummaryA major challenge in India is the frequent misdiagnosis of thalassemia as iron deficiency anemia, especially in primary care settings. Many patients receive repeated courses of iron supplementation without clinical improvement, while the underlying genetic disorder remains unrecognized.
First Oral Drug For Thalassemia: A Breakthrough—But Are We Diagnosing In Time?

Credit: Canva

For decades, thalassemia has been synonymous with lifelong blood transfusions, frequent hospital visits, and the persistent risk of iron overload. For patients and families, it has largely meant managing a chronic condition rather than truly treating it. That narrative, however, is beginning to change.

The recent approval of oral drugs for thalassemia by the US Food and Drug Administration marks a historic milestone. These oral, disease-modifying pyruvate kinase activators improve anemia in adults with non-transfusion-dependent (NTDT) and transfusion-dependent (TDT) \(\alpha\)- or \(\beta\)-thalassemia. For now, they are approved in the US and Saudi Arabia for adults with thalassemia, with European review ongoing.

It is offering a fundamentally different approach, one that targets the disease at its biological core rather than simply managing its complications. Yet, as this new era unfolds, a critical question remains: are patients being diagnosed early enough to benefit from it?

A shift from supportive care to targeted therapy:

Until recently, thalassemia management has depended heavily on blood transfusions and iron chelation therapy. While these interventions are life-saving, they do not correct the underlying defect in red blood cell production. Over time, repeated transfusions can lead to complications affecting vital organs such as the heart, liver, and endocrine system.

Oral drugs, however, work by activating pyruvate kinase in red blood cells, improving energy (ATP) production, and enhancing red cell survival. In simple terms, it helps the body produce more functional and longer-lasting red blood cells, leading to an increase in hemoglobin levels, reduced transfusion requirements, and improved quality of life, particularly with respect to fatigue, one of the most debilitating symptoms of the disease. Oral therapy working across a broader disease spectrum marks a significant advance.

India’s Hidden Burden

India bears one of the highest burdens of thalassemia globally, with an estimated 10,000–15,000 affected children born each year and a carrier frequency of approximately 3–4% in the general population. Despite this, a large number of cases remain undiagnosed or are diagnosed late, particularly in individuals with milder forms who may live for years with unexplained anemia.

Delayed diagnosis has far-reaching consequences. Patients may develop preventable complications, families miss opportunities for genetic counseling, and access to emerging therapies is delayed or entirely missed. In the era of precision medicine, such delays are no longer acceptable.

The Problem Of Misdiagnosis

A major challenge in India is the frequent misdiagnosis of thalassemia as iron deficiency anemia, especially in primary care settings. Many patients receive repeated courses of iron supplementation without clinical improvement, while the underlying genetic disorder remains unrecognized.

Certain clinical clues should prompt further evaluation: persistent microcytic anemia unresponsive to iron therapy, a family history of anemia or transfusion dependence, and a disproportionately high red blood cell count relative to hemoglobin levels. Diagnostic confirmation is straightforward with hemoglobin analysis using HPLC or electrophoresis; however, these tests are not always utilized at the appropriate time.

Diagnosis And Screening

The approval of oral drugs underscores a fundamental shift, from managing symptoms to modifying disease biology. However, these benefits are maximized when therapy is initiated early, before irreversible organ damage occurs, for which timely diagnosis is pivotal.

Thalassemia diagnosis begins with a complete blood count demonstrating microcytic anemia with low mean corpuscular volume and a relatively high red cell count. Peripheral smear findings include target cells and anisopoikilocytosis. Confirmation is achieved through hemoglobin analysis using HPLC or electrophoresis, which typically shows elevated HbA₂ in β-thalassemia trait. Molecular testing further identifies specific gene mutations, enabling definitive diagnosis and prenatal counseling.

Screening programs play a pivotal role. Carrier detection through HbA₂ estimation, premarital and antenatal screening, and cascade testing within families are essential strategies, particularly in high-prevalence populations like India.

The mutation spectrum in India is well characterized. The most common β-thalassemia mutation is IVS-I-5 (G→C), accounting for nearly half of cases, followed by IVS-I-1 (G→T), codon 41/42 deletion, codon 8/9 insertion, and the 619 bp deletion. In α-thalassemia, the –α³․⁷ deletion predominates. This knowledge allows for cost-effective targeted molecular screening.

For years, the central question in thalassemia was: how do we manage this disease?

Today, it is shifting to: how early can we treat it effectively? Oral drugs represent a major therapeutic advance; however, cost considerations, accessibility, and long-term real-world outcomes will influence their widespread adoption. Nevertheless, the direction is clear: thalassemia care is entering a transformative era. In modern medicine, early diagnosis is no longer just beneficial; it is truly transformative.

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Hantavirus: How Andes Strain Spreads Between Humans; Why It’s Not Another Pandemic

Updated May 10, 2026 | 07:34 AM IST

SummaryThe Andes virus is a rare but highly dangerous pathogen of hantavirus, found primarily in Argentina and Chile. It is the only type of hantavirus known to man to spread among humans.
Hantavirus: How Andes Strain Spreads Between Humans; Why It’s Not Another Pandemic

Credit: AI generated image

While the confirmation of the Andes strain of hantavirus behind the outbreak aboard the cruise ship MV Hondius in the South Atlantic has raised significant concerns of human-to-human transmission, experts from the International Hantavirus Society, as well as the World Health Organization (WHO), stated that the situation does not raise the risk of a pandemic.

So far, eight cases have been reported, including three deaths. The WHO has also confirmed that six cases have tested positive for the Andes virus, which can spread from person to person, through PCR testing.

The International Hantavirus Society, in a statement, warned that the virus differs significantly from most other hantaviruses because it can spread between people.

Founded in 2001, the Hantavirus Society is a global organization of scientists, clinicians, and researchers focused on studying hantaviruses, including their ecology, pathogenesis, and prevention.

“The virus on board the MV Hondius is the Andes strain of hantavirus. It is serious,” said the WHO chief Tedros Adhanom Ghebreyesus, in an open statement on the social media platform X.

However, the WHO and the members of the Hantavirus Society maintained that the current outbreak is not another COVID-19 outbreak.

So, first, let us understand all about the Andes Virus.

What Is Andes Virus

The Andes virus is a rare but highly dangerous pathogen of hantavirus, found primarily in Argentina and Chile. It is the only type of hantavirus known to man to spread among humans.

Unlike many hantaviruses seen in Europe, Asia, and North America, which are typically transmitted from infected rodents to humans, the Andes virus has repeatedly shown evidence of person-to-person spread.

As per experts, transmission usually occurs in situations involving prolonged or close contact. But how close is a question that has been recurring. The Hantavirus Society answers this.

“Over the past decades, multiple outbreak investigations, household clusters, nosocomial events, and genomic analyses have provided convincing evidence that ANDV can be transmitted between individuals under specific close-contact conditions. These may include household exposure, intimate contact, caregiving without suitable personal protective equipment, and prolonged exposure in poorly ventilated or crowded settings,” it said.

Pointing out decades of outbreak investigations, hospital clusters, and genetic studies, experts emphasized: “Human-to-human transmission of Andes virus should no longer be considered hypothetical”.

The scientists stressed that current evidence does not suggest the virus spreads easily through casual community interaction in the way diseases like measles, influenza, or COVID-19 do.

Also Read: Hantavirus Outbreak: How MV Hondius Passengers Will Be Screened And Evacuated

Andes Virus: High Fatality Rate A Concern

But the Andes virus is associated with hantavirus pulmonary syndrome (HPS) — a severe respiratory illness that can rapidly become fatal. Reported fatality rates range from 20% to 40%, depending on the outbreak setting, quality of medical care, and surveillance capacity.

Recent surveillance data highlight the seriousness of the disease:

  • Argentina reported 86 confirmed hantavirus cases in 2025, including 28 deaths.
  • Chile reported 35 confirmed cases, including 7 deaths.
Although annual case numbers remain relatively low, experts caution that this mainly reflects the rarity of exposure to infected rodents — not the absence of transmission risk once a human infection occurs.

Why Continuous Monitoring Is Important?

The first major indication of person-to-person transmission emerged during the 1996 El Bolsón/Esquel outbreak. More recently, the 2018–2019 Epuyén outbreak infected 34 people after a single index case attended crowded social gatherings while symptomatic.

Strict public health interventions — including isolation, quarantine, and active contact tracing — reduced transmission.

Read More: Hantavirus: Israel Confirms 1st Case as UK, Spain Probe Suspected Infections; Should You Be Worried?

The Hantavirus Society noted that a confined environment aboard the MV Hondius means that passengers and crew may still be within the virus’s incubation period.

The scientists thus warned, "A negative PCR test shortly after exposure does not necessarily rule out future infection.” They recommend “ongoing monitoring, repeat testing where necessary, and antibody testing for close contacts”.

Experts are also examining whether transmission could occur during early or minimally symptomatic stages, rather than only after obvious illness begins.

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