Why Tonsils Get Removed? The Science Behind It

Tonsils get removed when they cause more harm than good — most often because of repeated infections, chronic inflammation, or sleep-disordered breathing that blocks the airway. The surgery, called a tonsillectomy, is one of the oldest operations in medicine, and the reasons for doing it have shifted a lot over the past century. Today it is not about “getting rid of a useless organ.” It is about removing tissue that has become a persistent source of illness or obstruction.

Why Tonsils Get Removed: The Core Reasons

There are two main reasons surgeons remove tonsils: infection and obstruction. Most other reasons are variations on these two.

The infection reason is straightforward. The tonsils are part of the immune system’s first line of defense at the back of the throat. They trap bacteria and viruses that enter through the mouth and nose. That job comes with a cost. The same crypts and folds that catch germs can also harbor them, and in some people this leads to recurring tonsillitis or chronic infection that never fully clears.

The obstruction reason is different. Enlarged tonsils can physically narrow the airway, especially during sleep. This can cause snoring, pauses in breathing, and disrupted sleep. In children, this can affect behavior, school performance, and growth.

Understanding which problem is driving symptoms matters, because the treatment decision and the expected benefit are different for each.

What Makes a Surgeon Recommend Tonsillectomy?

Doctors do not remove tonsils just because they are large or because a child had a few sore throats. There are established criteria that guide the decision.

For recurrent throat infections, the widely used threshold is a specific frequency of documented episodes over a set period. The classic guideline traces to research published in the journal Otolaryngology–Head and Neck Surgery, which set criteria like seven or more episodes in one year, or five or more episodes per year for two consecutive years, or three or more per year for three consecutive years. Each episode needs to be documented — a positive strep test, a fever over 38°C (100.4°F), swollen lymph nodes, or pus on the tonsils. A parent’s memory of “a lot of sore throats” does not meet the bar.

For sleep-disordered breathing, the criteria are different. Here the concern is the airway, not infection. A child who snores loudly, pauses breathing during sleep, or has labored breathing at night may be evaluated for obstruction. In these cases, the size of the tonsils and adenoids, plus sleep study findings when available, drive the decision.

Some clinicians also recommend tonsillectomy for a peritonsillar abscess that does not respond to drainage, or for a history of recurrent abscesses. This is a less common pathway but a real one.

How the Immune System Copes Without Tonsils

This is where a lot of people worry unnecessarily. The tonsils are not the only immune tissue in the throat. They are part of a ring of lymphoid tissue called Waldeyer’s ring, which includes the adenoids, the lingual tonsils at the base of the tongue, and other smaller collections of tissue.

When the palatine tonsils are removed, the rest of this ring continues to do the same job. The immune system as a whole has many other sites — lymph nodes, the spleen, the thymus, and mucosal tissue throughout the gut and airways — that handle immune surveillance.

What does the research show about immune function after tonsillectomy? The evidence indicates that overall immune function is not meaningfully impaired. Some studies have looked at immunoglobulin levels and infection rates after surgery and found no significant long-term deficits. That said, the tonsils are not inert tissue, and removing them does remove one site of immune activity. The body compensates through the remaining lymphoid tissue. This is a well-established point, not a controversial one.

What Changes After Tonsillectomy?

The expected benefits depend on why the surgery was done.

For recurrent infection, the goal is fewer throat infections. Research consistently shows that tonsillectomy reduces the frequency and severity of throat infections in people who meet the criteria. It does not eliminate all sore throats — people can still get pharyngitis from viruses or other sources — but the recurring, severe episodes typically decrease.

For sleep-disordered breathing, the goal is better breathing during sleep. Studies show that most children who have tonsillectomy for obstructive sleep apnea see improvement in breathing, sleep quality, and daytime behavior. In some children, especially those with other risk factors, the sleep apnea does not fully resolve, and additional treatment may be needed.

Recovery takes time. The throat is raw and painful for roughly one to two weeks. Pain often peaks around days five to seven after surgery, which surprises many people who expect steady improvement from day one. Eating and drinking can be difficult, and dehydration is a common reason for readmission. Bleeding is a rare but serious complication and can occur during recovery, sometimes several days after surgery.

Why Tonsillectomy Rates Have Changed Over Time

Tonsillectomy was once performed far more often than it is now. In the mid-20th century, it was almost a rite of passage for children in some countries. Rates have dropped substantially since then.

The reasons for the decline are worth understanding. Better antibiotics meant fewer severe strep complications. More importantly, the criteria tightened. Research showed that many children who had their tonsils removed did not meet the thresholds that would justify the surgery. The shift was toward evidence-based selection rather than routine removal.

Today, the operation is more targeted. It is done when there is a clear pattern of infection or a clear airway problem. The pendulum has not swung back — it settled on a more selective approach based on documented criteria.

What About Partial Removal?

Some surgeons now perform a partial tonsillectomy, also called a subtotal or intracapsular tonsillectomy. In this approach, most of the tonsil tissue is removed but a small rim is left behind.

The idea is to reduce pain and bleeding risk during recovery. The trade-off is that the remaining tissue can regrow or become infected again, and in some cases a second surgery is needed. The evidence on whether partial removal is better overall is mixed. Some studies suggest faster recovery and fewer bleeding complications; others show higher rates of regrowth and repeat surgery. The choice depends on the reason for surgery, the surgeon’s experience, and the patient’s specific situation.

This is one of those areas where the “best” approach is not fully settled. It is a reasonable option in some cases, not a universal improvement.

When Surgery Is Not the Answer

Not every case of large tonsils or sore throats needs surgery. Many children with enlarged tonsils have no breathing problems and outgrow the issue as the throat grows. Many adults with occasional tonsillitis never meet the criteria for removal.

Watchful waiting is a legitimate option when symptoms are mild or infrequent. For sleep-disordered breathing, some children improve with treatment of allergies or other contributing conditions. For recurrent infections, the frequency and severity over time determine whether the criteria are met.

The decision should rest on documented symptoms, not on a single bad episode or a parent’s worry. That said, when the criteria are met, the evidence supports surgery as an effective option.