US Trends

what is a non secretor blood type

A non‑secretor blood type isn’t a separate blood group like A, B, AB, or O – it’s about whether your usual ABO blood type “shows up” in your body fluids (like saliva, mucus, tears, semen, etc.) or not.

What is a non‑secretor blood type?

In the secretor system, people fall into two broad categories:

  • Secretors : Their ABO blood group antigens (A, B, or H for type O) are present on red blood cells and dissolved in body fluids such as saliva, tears, mucus, and other secretions.
  • Non‑secretors : They have a normal ABO blood type on their red blood cells, but they do not secrete those ABO antigens into body fluids.

So when someone says they are a “non‑secretor blood type,” it usually means: “I’m, for example, blood type A, but I do not secrete A (or H) antigens in my saliva or other secretions.”

Key points in simple terms

  • Your main blood type (A, B, AB, or O) is unchanged; secretor status is an extra layer of classification.
  • Being a non‑secretor is controlled by a separate gene (often called Se/se) that is independent of the ABO gene.
  • Non‑secretors lack water‑soluble ABO antigens in fluids like saliva, tears, and mucus; secretors have them.
  • A person can be: A secretor, A non‑secretor, B secretor, B non‑secretor, AB secretor, AB non‑secretor, O secretor, or O non‑secretor.

How common is non‑secretor status?

  • In many populations, about 15–20% of people are non‑secretors, while 80–85% are secretors.
  • Exact percentages vary by ethnic group and region, but non‑secretors are always a minority compared to secretors.

How is non‑secretor status tested?

Secretor status usually doesn’t show up on a routine blood type report. It needs special testing:

  1. A lab collects saliva or sometimes blood.
  2. They test for the presence or absence of soluble A, B, or H antigens in that saliva/serum.
  3. If the antigens are present → secretor; if not → non‑secretor.

These tests are sometimes done in:

  • Specialized medical or research labs.
  • Forensic labs, because knowing if someone is a secretor can help interpret traces of saliva or semen at a crime scene.

Why do people care about non‑secretor status?

Doctors do not use secretor status the way they use ABO or Rh for transfusions or pregnancy, but it shows up in a few areas of interest.

1. Infection and immunity

Because antigens in saliva and mucus can interact with microbes, secretor status may slightly influence susceptibility to some infections:

  • Non‑secretors have different patterns of antigens on mucosal surfaces, which can change how certain bacteria or viruses attach.
  • Some research links non‑secretor status to different risks for gut, respiratory, or urinary infections, but the picture is complex and not fully settled.

2. Blood clotting and cardiovascular risk (research/controversial)

Naturopathic and some research‑oriented sources suggest that:

  • Non‑secretors, particularly type A non‑secretors, may have thicker blood, shorter bleeding times, and a higher tendency for platelet aggregation.
  • This could be associated with higher risk of atherothrombotic events (like certain heart or vessel problems), though this is not a standard clinical test in cardiology.

This area is still being studied and is not used as a routine risk score in mainstream medicine.

3. Digestive tract and microbiome

Some work suggests that secretor status affects:

  • The types of bacteria that colonize the gut (since antigens in mucus can serve as “food” or attachment sites).
  • Intestinal enzymes and immune responses on mucosal surfaces.

Again, this is mostly research/functional‑medicine territory, not standard primary‑care screening.

4. Blood type diets and alternative health

Secretor vs non‑secretor became popularized by Dr. Peter D’Adamo’s “blood type diet” and related books/websites:

  • These systems propose different diet and lifestyle tweaks depending on both ABO type and whether you are a secretor or non‑secretor.
  • Many people on forums discuss being “O non‑secretor” or “A non‑secretor” in relation to specific diet plans, dental issues, or autoimmune concerns.

Mainstream medical consensus is that evidence for individualized “blood type diets” is limited, so this is best viewed as optional lifestyle experimentation, not a proven medical rule.

Genetics in a nutshell

  • Secretor gene: often denoted Se (functional) and se (non‑functional).
  • Se is usually dominant over se. That means:
    • SeSe or Sese → secretor.
    • sese → non‑secretor.
  • This gene acts in glands that produce saliva, mucus, etc., determining whether they add ABO antigens to those secretions.

Your ABO gene still decides whether you are A, B, AB, or O; the secretor gene just adds a “yes/no” flag for putting those antigens into body fluids.

Mini FAQ: non‑secretor blood type

1. Does being a non‑secretor change which blood I can receive?
No. Transfusion safety depends on your ABO and Rh types, not secretor status.

2. Is being a non‑secretor dangerous?
On its own, no. It’s a normal genetic variant found in a sizable minority of people. Some research suggests slightly different risk profiles for certain conditions, but nothing as dramatic as a “dangerous blood type.”

3. Can I tell if I am a non‑secretor from a regular blood test?
Typically no; you need a special secretor‑status or saliva antigen test.

4. Is secretor status “latest news” or a trending topic?
It pops up periodically in:

  • Alternative health and nutrition communities (especially blood type diet followers).
  • Microbiome and personalized‑medicine discussions.
  • Forensic and genetic hobbyist forums, where people talk about how saliva DNA or antigen patterns work.

So it keeps resurfacing as a “hidden blood type detail” people discover and discuss online.

Quick recap (TL;DR)

  • A non‑secretor blood type means you have a normal ABO type but do not secrete those ABO antigens into saliva and other body fluids.
  • It is controlled by a separate gene (Se/se), independent of ABO.
  • Around 15–20% of people are non‑secretors, depending on population.
  • It can have subtle links to infections, clotting, and gut/microbiome research, and is often discussed in blood‑type‑diet and alternative‑health circles, but it is not a routine clinical test.

Information gathered from public forums or data available on the internet and portrayed here.