Who Can Donate Blood To Whom?

Updated Dec 8, 2024 | 01:00 AM IST

Summary Learn who can donate blood to you and who you can donate to, plus the importance of blood types, Rh factors, and why O-negative is a universal donor.
Who can donate blood to whom?

Credits: Canva

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

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First Trimester Miscarriages: Gynae Blames It On Undiagnosed Insulin Resistance

Updated Apr 20, 2026 | 07:00 PM IST

SummaryWhen it comes to women's health, every aspect makes a lot of difference. According to experts, insulin resistance is a common cause of miscarriages.
Miscarriage

Pregnant women must go for regular health check-ups to ensure that there are no hidden complications that may show up later. (Photo credit: iStock)

Insulin resistance is a condition in which the body cannot effectively use insulin. Shockingly, this condition is now being linked to first-trimester miscarriages, especially in women with PCOS, with lab markers such as HbA1c and fasting insulin offering early clues. Therefore, it is essential for women to take charge of their health and maintain their blood sugar levels within the recommended range, as per Dr Sushruta Mokadam, Senior Consultant Obstetrician & Gynaecologist, Motherhood Hospital, Kharadi, Pune. The expert went on to talk about other aspects of the same, detailing just how first trimester miscarriages could be a consequence of ignoring high blood sugar or insulin resistance.

Why are miscarriages in the first trimester rising?

Currently, there is a surge in cases of miscarriages during the first trimester, which is raising concern among experts. This may be due to undiagnosed insulin resistance. Yes, that’s right—miscarriage is not only caused by infections, hormonal imbalance, or blood clotting disorders, but also by insulin resistance. Many women fail to pay attention to insulin resistance, which affects how the body processes sugar and plays a major role in causing hormonal imbalance. Women with Polycystic Ovary Syndrome (PCOS) are at a higher risk, as metabolic dysfunction can lead to miscarriage. Many women are experiencing repeated early pregnancy loss but are not screened for insulin resistance, leading to missed opportunities for early intervention.

How are miscarriages and insulin resistance linked?

Miscarriage and insulin resistance link: Insulin resistance occurs when the body’s cells do not respond properly to insulin, leading to higher blood sugar and insulin levels. This imbalance can impact ovulation and egg quality and interfere with the implantation of the embryo. In early pregnancy, it may affect placental development, increasing the risk of miscarriage in the first trimester. In women with PCOS, insulin resistance is commonly present, even in those who are not overweight.

The impact of insulin resistance on reproductive health

High insulin levels can lead to increased androgen (male hormone) production, further affecting reproductive health. This hormonal imbalance can make it difficult for a pregnancy to be sustained, especially in the early weeks, which may result in miscarriage. Lab tests such as HbA1c (which reflects average blood sugar levels over time) and fasting insulin levels can help identify at-risk women. Even subtle elevations in these markers, including those within the upper-normal range, can indicate underlying metabolic dysfunction that may increase the chances of miscarriage.

What to do?

Pregnant women should opt for regular screening, manage blood sugar levels, eat a balanced diet, and exercise daily before planning pregnancy. Even during pregnancy, they should stay in touch with an expert who can guide them throughout the process.

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Ideal Blood Pressure Reading for Older Adults: Harvard Health Experts Have an Answer

Updated Apr 20, 2026 | 09:00 PM IST

SummaryEssential hypertension refers to a state wherein rising blood pressure is for the benefit of older adults.
Hypertension

Uncontrolled hypertension is potentially fatal. (Photo credit: iStock)

Blood pressure is one of the most important, yet overlooked, aspects of a healthy individual. Little do people realise that the force at which blood presses against the walls of the arteries can have a serious impact on long-term health—heart attack or stroke, for instance. Current guidelines from the American Heart Association state that adults should aim for a blood pressure reading of 130/80 millimetres of mercury (mm Hg). Some experts also say that this target is a little too aggressive for people who are prone to the side effects of blood pressure medication, such as falls and dizziness. But what would be the ideal blood pressure reading for older adults? Harvard Health experts have just answered this question.

Blood pressure reading in the 60s

According to recent studies, an intensive reduction in blood pressure in people aged over 60 is not only safe but is also associated with better outcomes than less aggressive treatment. According to a 2025 review, four randomised controlled trials were compared using two different strategies to control systolic blood pressure. The first aimed for a lower target, while the other strategy aimed for a higher systolic pressure. The trial included 2,600 people aged 75 years and older. Compared with a less aggressive strategy, there was a 39 per cent reduced risk of heart problems such as heart failure, heart attack, or stroke. There was also a 45 per cent lower risk of heart disease-related deaths.

Additionally, researchers noted no differences in the rates of adverse events such as fractures, low blood pressure, cognitive decline, or falls. Upon expanding the analysis, the same conclusions held true for people aged 70 years and above.

Rising hypertension risk

The risk of hypertension rises significantly with age. Among ageing adults, it is known as essential hypertension, as it helps deliver a sufficient amount of blood to the brain. With age, the blood vessels become less flexible and stiffer. Therefore, to reach the brain, an extra push is needed—as a result, systolic blood pressure can rise to as high as 150 mm Hg in people aged 65 years and above.

Doctors, however, are reconsidering their approach to hypertension treatment in older adults. The recent findings suggest that many older people should aim to keep their systolic pressure below 130 mm Hg. This may require a combination of lifestyle changes and medication.

Can one medication work?

According to experts, one medication may not be sufficient to achieve ideal blood pressure. A single drug usually works well to lower blood pressure by an average of 5 to 10 points. Using a lower dose of two different blood pressure medicines is more effective than maximising the dose of one drug. This approach is also less likely to result in side effects.

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Explained: The Hidden Link Between Cortisol, Metabolic Changes And Liver Function

Updated Apr 20, 2026 | 09:00 AM IST

SummaryThe stress hormone cortisol can weaken the liver when excess is released over a short period of time.
stress (1)

Chronic stress can also result in belly fat accumulation. (Photo credit: iStock)

The relationship between chronic stress and liver health is a complex physiological loop driven largely by cortisol, the body’s primary stress hormone. While the liver is often viewed as a detox organ, it is highly responsive to hormonal signals, especially during prolonged stress. But at a time when competition is at its all-time peak in every aspect of life, be it work or school, it is a no-brainer that stress levels are peaking across age groups. That being said, Dr. Tushar Madake, Consultant, Department of Transplant Hepatology at Ruby Hall Clinic, Pune, spoke about the impact of high cortisol on the liver.

What is cortisol?

When stress becomes chronic, the adrenal glands continuously release cortisol. The liver, rich in glucocorticoid receptors, responds by shifting into a survival mode. In short-term situations, this helps by releasing glucose into the bloodstream for quick energy. However, when stress persists without physical activity, this constant signal disrupts normal metabolism.

The impact of high cortisol levels

One major effect is increased glucose production, where the liver generates sugar from non-carbohydrate sources. Over time, this leads to consistently high blood sugar and forces the pancreas to produce more insulin, eventually contributing to insulin resistance. At the same time, cortisol promotes the release of fatty acids into the bloodstream. The liver absorbs these fats but struggles to process and export them efficiently, leading to elevated triglycerides and unhealthy cholesterol levels.

How does stress affect the liver?

Stress also drives fat storage in the abdominal region and within the liver itself. This can result in fatty liver disease, even in individuals without poor dietary habits. As fat accumulates, inflammation follows. Liver immune cells release inflammatory substances, creating oxidative stress that damages liver cells. Additionally, when the liver is overloaded with managing excess glucose and fat, its ability to detoxify the body declines. Hormone balance, toxin clearance, and medication metabolism are all affected.

Stress can also impair bile flow, which is essential for fat digestion and toxin removal. Reduced bile movement further worsens internal imbalance. Ultimately, chronic stress keeps the liver in a constant state of overdrive, leading to long-term metabolic strain, inflammation, and gradual liver dysfunction.

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