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.

Do you often forget where you kept your keys or glasses and worry that it could be a sign of Alzheimer's disease? While many people become more forgetful with age, doctors say that occasional memory lapses are a normal part of ageing. Alzheimer's disease, however, causes a different pattern of decline that affects memory, thinking and the ability to function in everyday life.

HealthandMe spoke to two neurologists who explained how to tell the difference between normal age-related forgetfulness and the warning signs of Alzheimer's disease.

"Many people worry when they start becoming more forgetful with age. While some changes in memory and thinking are a natural part of growing older, Alzheimer's disease causes a different pattern of decline that affects everyday life," said Dr. Rajneesh Kummar, Vice Chairman & Unit Head, Neurology, Max Super Speciality Hospital, Dwarka.

Dr. Praveen Gupta, Chairman, MAIINS, Marengo Asia Hospitals, Gurugram, added, "Alzheimer's is not a normal part of ageing. It's a neurodegenerative disease that affects memory, thinking and how you function each day. Recognising the difference can help people get medical evaluation and treatment sooner."

Also read: India Gets Its First Alzheimer’s Drug: Know All About Eli Lilly’s Lormalzi

The experts advised that persistent memory concerns should not be ignored. If symptoms become more noticeable or begin affecting day-to-day functioning, a medical assessment can help identify the cause and guide appropriate treatment and support.

They outlined six key differences that can help distinguish normal ageing from Alzheimer's disease.

1. Occasional Forgetfulness vs Repeated Memory Loss

According to the doctors, it is common to occasionally misplace items, forget a name or an appointment, and remember the information later.

However, people with Alzheimer's disease may repeatedly forget recent events, conversations, appointments or newly learned information and may not recall them even after reminders.

2. Slower Thinking vs Difficulty With Everyday Tasks

Normal ageing may mean taking longer to learn new technology or complete routine tasks.

In Alzheimer's disease, people may struggle to manage bills, prepare meals, follow directions, learn to use a new phone or remember instructions given only moments earlier.

3. Misplacing Things vs Forgetting They Were Ever There

Occasionally losing keys or glasses is considered a normal part of ageing, and most people can usually retrace their steps and find them.

By contrast, people with Alzheimer's disease may not remember putting an item down or even recall recently getting or buying it.

Read More: Anti-Inflammatory Diet May Help Lower Dementia Risk, Even In Those Who Show Early Signs Of Alzheimer’s: Study

4. Temporary Confusion vs Disorientation

Older adults may occasionally lose track of the day or date but usually remember it shortly afterwards.

According to the doctors, Alzheimer's disease can cause confusion about time, dates and places. People may repeatedly ask the same questions or become disoriented, even in familiar surroundings.

5. Searching for Words vs Difficulty Communicating

Everyone experiences occasional "tip-of-the-tongue" moments.

With Alzheimer's disease, people may frequently lose their train of thought, repeat themselves, struggle to follow conversations or have difficulty finding the right words.

6. Remaining Independent vs Needing Increasing Support

The doctors said one of the biggest differences is that normal ageing generally does not prevent a person from living independently.

Alzheimer's disease, however, gradually affects a person's ability to carry out everyday activities, adapt to changes in routine and maintain self-care without assistance.

Bryan Johnson, the billionaire biohacker and longevity enthusiast, has been diagnosed with an incurable autoimmune disease called Autoimmune Gastritis (AIG).

Johnson is known for his radical longevity experiments, including measuring the biological age of his organs in an effort to reverse aging, injecting himself with ketamine, taking over 50 pills a day, undergoing fat transfers, and receiving blood transfusions from his teenage son.

In a recent post on X, he made the shocking announcement of his autoimmune conditions, which went undetected for years: Autoimmune Gastritis.

Calling it "bad news," Johnson wrote: "I have an autoimmune disease. My stomach is eating itself."

"2-5 per cent of people have this, too. Likely more, because it hides," he added.

According to Johnson, his stomach had been attacking itself without causing noticeable symptoms. The condition was only discovered in May.

Also read: Bryan Johnson Blames Sugary Cereals, Soda and Stress for His Autoimmune Disease; Shares Treatment Plan

The Early Warning Sign: Low Ferritin

Autoimmune Gastritis, a condition in which the immune system attacks the stomach's acid-producing cells, also impairs the absorption of iron and vitamin B12.

Johnson said one of the earliest signs of the condition was persistently low ferritin levels over the past 11 years despite not having anemia.

"We continually tried to raise my iron levels with food and supplementation, but nothing would work."

He said he followed a plant-based diet, trained intensely, used a sauna and hyperbaric oxygen therapy, and took iron supplements, yet his iron levels remained low.

Ferritin stores the body's iron. Iron is essential for transporting oxygen and producing energy, and low iron levels can lead to fatigue, weakness, and dizziness.

Johnson said autoimmune gastritis is difficult to diagnose because its earliest clue is often overlooked.

"The earliest clue, low ferritin, is the one standard medicine waves through. Low iron stores get normalized and rarely investigated at all when anemia hasn't shown up yet. That blind spot is what hid mine for a decade."

While initially it wasn't clear why his iron levels were continuously dipping, after further testing, Johnson's team identified three interconnected issues.

Read More: Bryan Johnson Battles Autoimmune Gastritis: Which Parts Of His Longevity Guide Are Actually Worth Copying?

Autoimmune Gastritis was preventing normal iron absorption by damaging the stomach cells that produce acid. He also discovered autoimmune thyroid disease.

"The iron deficiency, the autoimmune gastritis driving it, and the autoimmune thyroid disease alongside it. Iron and thyroid feed each other both ways; low iron impairs the conversion of thyroid hormone into its active form, and an underactive thyroid impairs how the body uses iron," Johnson explained.

Iron Deficiency May Be More Common Than Many Realize

According to research published in JAMA Network Open, about one in four Americans may have inadequate iron intake or absorption.

As per the study of more than 8,000 Americans, 14 per cent of adults had absolute iron deficiency, reflecting depleted iron stores.

Even after excluding common causes such as anemia, pregnancy, heart failure, and chronic kidney disease, 11 per cent remained iron deficient. Another 15 per cent had functional iron deficiency, where iron levels appear normal but the body cannot use the mineral effectively.

How Bryan Johnson Is Managing The Condition

Since receiving the diagnosis, Johnson has begun iron infusions, which deliver a full dose of iron in a single treatment.

He said his team will continue routine monitoring of his ferritin and iron levels.

Johnson ended his post with a warning that hidden health conditions can go unnoticed for years.

"You too may have a lurking health issue that is undiagnosed and could increase in severity from unhealthy life choices, without your knowing… A gentle nudge that minding your health, no matter your situation in life, is a good decision-making."

A recent study has indicated that following a healthy diet consistently may help reduce the risk of dementia, even in those who already show early signs of Alzheimer's disease. The study could help in early management of neurodegenerative diseases like dementia.

Anti-Inflammatory Diet May Help Lower Dementia Risk

According to a new study published in the JAMA Network Open, scientists found that participants who maintained better-quality diets over a period of 15 years were less likely to develop dementia, regardless of whether their blood tests indicated the presence of Alzheimer ’s related biomarkers.

The findings also suggest that healthy eating habits may benefit even after the individual shows signs of the disease processes have begun.

About The Study And Its Results

The researchers followed middle-aged and older adults one and a half decades, examining their dietary habits alongside blood biomarkers associated with Alzheimer's disease, including phosphorylated tau217 (p-tau217), glial fibrillary acidic protein (GFAP), and neurofilament light (NfL).

These biomarkers are commonly used to detect early Alzheimer's-related changes and neurodegeneration before symptoms of the disease become visible.

The participants followed a healthy diet, particularly a Mediterranean-style as well as an anti-inflammatory diet. The findings showed that individuals with healthier diets had a lower risk of developing dementia over the follow-up period.

Remarkably, this association was observed even among participants who presented Alzheimer's biomarkers, indicating that diet may offer protective benefits despite early signs.

Alzheimer's disease begins years, and sometimes decades, before memory problems emerge. During this preclinical stage, abnormal proteins accumulate in the brain while individuals remain symptom-free.

Read more: New Blood Test May Predict Alzheimer's Symptoms At Least 4 Years In Advance: Study

The new findings indicate that lifestyle factors such as diet could still influence dementia risk even after these biological changes have started. This reinforces growing evidence that preventive measures need not be limited to people without detectable Alzheimer's pathology.

Not A Preventative Measure

While the study shows promising results of the effect of a healthy diet on the neurodegenerative disease, it does not prove that diets can directly prevent dementia.

The researchers emphasized that the study was merely an observation, meaning it highlighted an association rather than a direct cause-and-effect relationship. It just supports the idea that long-term healthy eating could have a significant impact on one’s brain health throughout adulthood.

Benefits Of Anti-Inflammatory & Mediterranean Diets

The anti-inflammatory diet, as recommended by Harvard Nutrition Source, helps calm the immune system by choosing foods that reduce inflammation.

This dietary approach encourages a balance of fruits, vegetables, healthy fats, whole grains, and other nutrient-dense foods while avoiding those that trigger inflammation.

On the other hand, Mediterranean diet, long celebrated for its heart-and longevity-promoting benefits, is now gaining attention for its beneficial effects on the brain.

This diet emphasizes plant-based foods, healthy fats such as extra virgin olive oil, nuts, fruits, vegetables, and whole grains, with moderate fish intake.

In another study published in Nature Medicine, researchers observed that individuals at the highest genetic risk for Alzheimer’s disease, particularly carriers of the APOE4 gene variant, showed the most significant reduction in dementia risk when adhering closely to this dietary pattern.