Do you know who can donate blood to you or who can you donate blood to? Blood donation may not be complex, but it does need to be compatible with yours and vice-versa. The blood types are determined by the presence or absence of certain antigens - substance that can trigger immune response if they are foreign to the body.

There are four major blood groups which are determined by the presence or absence of two antigens, A and B, on the surface of red blood cells. There is also a protein called the Rh factor, which can either be present (+) or absent (-), which creates A+, A-, B+, B-, O+. O-, AB+, AB- blood types.

Group A blood type has only A antigens on red blood cells and B antibody in the plasma. B has only B antigen on red cells and A antibody in the plasma. AB has both A and antigens on red cells, but neither A nor B antibody is present in the plasma. O has neither A nor B antigens on red cells, but both A and B antibody are present in the plasma.

Blood Type And Who Can You Donate To?

Your blood type determines who can you donate to. This is because there are very specific ways in which blood types must be matched for safe transfusion. The right blood transfusion could actually save you, while the wrong one could be lethal. Also, Rh-negative blood is given to Rh-negative patients and Rh-positive or Rh-negative blood can only be given to Rh-positive patients.

If you are O blood type, you can donate to O, A, B, and AB, if you are A blood type, you can donate to A and AB, if you are B blood type, you can donate to B and AB, however if you are AB, you can only donate to AB.

Who Can You Receive Blood From?

If you are O blood type, you can only receive from O. If you are A, you can receive from type A and O. If you are blood type B, you can receive from type B and O. If you are AB, you are lucky, you can receive blood from O, A, B, and AB.

There are more than 600 other known antigens, the presence or absence of which creates "rare blood types". Certain types are unique to specific ethnic or racial groups, this is why an African-American blood donation can be the best hope for the needs of patients with sickle cell disease, as per the Red Cross Organization.

Universal Blood Donor

Type O is one in high demand, as it can donate blood to anyone. O negative blood type is the universal blood type, which can donate to everyone, especially during the emergency transfusions and for immune deficient infants.

Who Have These Blood Types In US?

In the US, 37% Caucasian, 47% African-American, 39% Asians, and 53% Latino-American are O-positive. However, only 8% of Caucasian, 4% of African-American, 1% Asian, and 4% Latino=Americans are O-negative.

A+: 33% Caucasian, 34% African-American, 27% Asian, 29% Latino-American

A-: 7% Caucasian, 2% African-American, .5% Asian, 2% Latino-American

B+: 9% Caucasian, 18% African-American, 25% Asian, 9% Latino-American

B-: 2% Caucasian, 2% African-American, .4% Asian, 1% Latino-American

AB+:3% Caucasian, 4% African-American, 7% Asian, 2% Latino-American

AB-: 1% Caucasian, .3% African-American, .1% Asian, .2% Latino-American

Dry eyes are common among people who spend long hours on screens, and lubricating eye drops are often used for relief. But using the wrong drops, keeping an opened bottle for too long or even sharing eye drops can create problems.

Estimates suggest that up to 50% of adults experience dry-eye symptoms, making artificial tears a common part of self-care. But persistent symptoms should not simply be treated indefinitely without identifying the underlying cause.

So, how often can you use eye drops, and what should you keep in mind?

We spoke to Dr. Ritika Sachdev, Director at Centre for Sight, New Delhi, to understand the common mistakes people make while using eye drops.

Eye Drops For Dry Eyes: When Should You See A Doctor?

Dr. Ritika said persistent or bothersome dry eye symptoms should be assessed by a doctor because dryness can have several causes.

These may include:

• Eyelid inflammation
• Allergies
• Contact lens use
• Makeup
• Incorrect spectacle power causing eye strain

“Sometimes even not wearing your right spectacle power contributes to eye strain which can be misread as dry eye,” she said.

Lubricating drops can help support dry eyes, but prolonged use should be discussed with an eye specialist.

Using Eye Drops For Long? Check For Preservatives

Also read: Eye Drop Recall: Nearly 750,000 Products Pulled Over Sterility Concerns in US

Several eye-drop products have been recalled in the US in recent years over contamination and other safety concerns. This makes proper storage, handling and hygiene particularly important when using eye drops.

Dr. Ritika cautioned that some eye drops contain preservatives that may worsen dryness when used for a long time.

“Many of the eye drops have preservatives which if used over a long period of time actually cause more dry eye,” she said.

According to her, preservative-free drops or those with very mild preservatives may be preferable for people who need regular use.

Don't Keep An Open Eye Drop Bottle Forever

"Once opened, an eye drop bottle can become contaminated if it is not handled or stored properly," Dr. Ritika said.

The expert advised:

• Note the date when you open the bottle.
• Follow the product's storage instructions.
• Do not let the bottle tip touch your eye.
• Discard the bottle according to the manufacturer's instructions.
• Do not continue using an opened bottle indefinitely.

“Once the bottle is open, it often may get contaminated,” she said. “If it gets contaminated, it is a source of infection.”

Read More: Andrew Huberman’s Sleep Trick: Can Eye Movements Help You Fall Back Asleep?

How Many Eye Drops Should You Use?

More drops do not mean more relief.

“The capacity of the eye is only one drop,” Dr. Ritika said.

Putting two or three drops at once can cause the excess to spill onto the surrounding skin and simply waste the product. One properly administered drop is generally enough at a time, she said.

Avoid Squeezing Your Eyes After Using Drops

Dr. Ritika said people often squeeze their eyes tightly after putting in drops because they think this will keep the medicine inside. But squeezing can push the drop back out.

Instead:

• Gently pull down the lower eyelid.
• Place the drop into the eye.
• Avoid touching the bottle tip to the eye.
• Do not squeeze the eyes tightly immediately afterward.

Why Do Eye Drops Sometimes Reach The Throat?

Some people experience an unpleasant sensation in the throat after using medicated eye drops.

Dr. Ritika explained that tears can travel from the eye through the tear duct to the nose and then the throat.

She suggested gently pressing near the inner corner of the eye for a while after applying the drop to reduce this drainage.

Never Share Your Eye Drops

Sharing eye drops may seem harmless, particularly within families, but Dr. Ritika advised against it.

If the bottle tip accidentally touches an infected eye, the bottle can become contaminated and potentially transmit infection when used by someone else.

“Eye drop is something that is for your personal hygiene and it should therefore be kept by you and used by you,” she said.

Clear vision does not always mean that the eyes are healthy. Diabetes can damage the retina the sensitive layer at the back of the eye long before a person notices any change in eyesight.

This happens because high blood sugar can weaken the blood vessels that supply the retina causing them to leak fluid or blood.

What happens as retinopathy progresses?

Diabetic retinopathy is a complication in which high blood sugar damages the blood vessels. In the stages these vessels may swell or develop small areas of bleeding without affecting vision.

As the condition advances, reduced blood supply can cause abnormal new blood vessels to grow. These vessels are fragile. May bleed into the vitreous the clear gel inside the eye. In some cases, scar tissue can pull the retina away from its normal position leading to retinal detachment and potentially permanent vision loss.

Also read: Eye Drop Recall: Nearly 750,000 Products Pulled Over Sterility Concerns in US

How diabetes affects central vision

Diabetes can also affect the macula, the part of the retina responsible for sharp detailed vision. When fluid builds up in this area it can cause macular oedema and gradually affect the quality of vision.

It may lead to:

• Distorted central vision
• Difficulty reading or recognising faces
• Problems with activities that require clear detailed vision, such as driving

Diabetic macular oedema can occur at different stages of diabetic retinopathy and does not always cause symptoms in the early stages.

Also read: Eye Twitching: Is It Just Stress Or Something Serious?

Who is at risk?

The likelihood of eye damage increases with the duration of diabetes and poor blood sugar control. High blood pressure, abnormal cholesterol levels and kidney disease can further increase the risk.

Women with diabetes may also need monitoring during pregnancy as hormonal and blood sugar changes can worsen existing retinal disease.

Why regular eye examinations matter

On World Sight Day, doctors recommend that a routine eyesight test may not detect damage to the retina. People with diabetes should therefore undergo an eye examination, including a dilated retinal examination at intervals recommended by their ophthalmologist.

Keeping blood sugar, blood pressure and cholesterol, under control can help reduce the risk of complications. If damage is detected treatment may include eye injections, laser therapy or surgery depending on its severity.

Diabetic eye disease can often be managed effectively when identified early. Regular retinal examinations remain important when a person can see clearly as changes may develop before symptoms appear.

By Dr Ashu Agarwal, Senior Consultant, Opthalmology, Indraprastha Apollo Hospital, Delhi

Menopause is a natural stage of aging that ends menstruation and reproductive function. It usually occurs between ages 45 and 55.

But growing interest in extending the reproductive years has raised a question: Can menopause be delayed, and would doing so actually benefit women's health?

Longevity influencer Kayla Barnes-Lentz, in her mid-30s, recently told Business Insider that she is trying to delay menopause until 60 using lifestyle changes and experimental treatments.

Can Menopause Be Delayed?

Scientists are studying ways to slow ovarian aging, including ovarian tissue freezing and drugs such as rapamycin.

Early human research suggests rapamycin may slow ovarian aging by around 20%. However, evidence remains limited, and the drug is not FDA-approved for delaying menopause. Its use for this purpose is off-label.

The 2024 Research by Dr. Kutluk Oktay at Yale School of Medicine has also explored whether menopause could eventually be postponed or prevented by preserving ovarian function.

But delaying menopause is not necessarily an all-round health benefit. Longer estrogen exposure may support bone, heart and brain health, while potentially increasing the risk of some hormone-sensitive cancers.

What Are The Risks Of Early Menopause?

Also read: ‘I Was Vocal About Cancer But Silent About Menopause Out Of Shame’, Says Actress Lisa Ray

Menopause around age 45 or younger can affect several aspects of health as estrogen levels fall.

• Bones: Faster bone loss and higher osteoporosis risk.
• Heart: Changes in blood vessels and cholesterol may increase cardiovascular risk.
• Brain: Hormonal changes can affect memory and cognition.
• Sexual health: Vaginal dryness and reduced lubrication can cause discomfort.
• Urinary health: Lower estrogen can contribute to urinary symptoms and incontinence.

Is Later Menopause Healthier?

Menopause at 55 or older means longer exposure to estrogen and has been associated with some benefits, including better bone and cardiovascular health.

But the picture is not straightforward. Longer estrogen exposure has also been linked to a higher risk of breast, endometrial and ovarian cancers. So, later menopause should not automatically be considered healthier.

Can HRT Delay Menopause?

No. Hormone replacement therapy treats menopause symptoms but does not stop or postpone menopause.

It can help with hot flashes, sleep problems and vaginal dryness and may benefit some women at risk of bone loss. HRT can contain estrogen alone or estrogen with progesterone.

Its risks and benefits depend on factors such as age, timing, formulation, dose and duration. For appropriate women, the benefit-risk balance is generally more favorable when treatment begins before age 60 or within 10 years of menopause.

Can lifestyle delay menopause?

Genetics play a major role in determining when menopause occurs, and there is no lifestyle change proven to reliably postpone it.

Some factors have been linked with later menopause or a lower risk of early menopause:

• Breastfeeding: Longer breastfeeding has been associated with a lower risk of early menopause.
• Exercise: Supports overall health, although evidence that it directly delays menopause is limited.
• Not smoking: Smoking is linked to earlier menopause.
• Healthy diet: Some research links diets rich in antioxidants and omega-3 fatty acids with later menopause.

These habits cannot guarantee a later menopause but can support overall health through midlife.

For now, treatments specifically designed to delay natural menopause remain experimental. There is no established method that can reliably and safely postpone menopause in healthy women.