Your normal blood tests may overlook serious illness

Your blood tests may say everything is "normal", but your body might be telling a very different story. Persistent symptoms such as fatigue, pain, or discomfort should not be brushed aside simply because lab results fall within a standard range.

On Wednesday, Dr Karan Rajan, a surgeon and content creator, shared via Instagram that blood tests are only one piece of the puzzle and that symptoms require careful evaluation.

Blood tests are “snapshots”

Dr Rajan explains that it is entirely possible to have normal results while experiencing recurring symptoms. Lab tests function as snapshots that can overlook long-term health trajectories.

• “For example, your HbA1c, which is a marker of long-term blood sugar control, could be 40 millimoles per mole, which is considered normal. But maybe last year it was 35 and the year before that 30. Your absolute number could be normal, but your trajectory could be concerning and it could signal that maybe you're headed towards a disease process. Blood tests without context are often very limited.”

Some conditions don’t show up on blood tests

Many diagnoses rely on medical history and clinical presentation rather than lab values.

• “But there's also many conditions that just don't show up in bloods. Endometriosis, fibromyalgia, many chronic pain conditions, early cancers, POTS. These are often clinical diagnoses based on symptoms, not just a lab value."

How to deal with a situation like this?

If symptoms persist despite normal reports, Dr Rajan recommends asking:

• "What conditions could present this way even with normal labs?"
• "Can I see my results from the last few visits to understand the trend?"
• "Are there any specialist blood tests that may be worth checking?"
• "Is there any value in imaging or referral to a specialist?"

The surgeon also suggests maintaining a detailed symptom diary to provide doctors with a clearer picture of triggers and patterns.

Please Note: This information is for educational purposes only and does not count as medical advice. Readers should always consult a qualified doctor regarding any questions about their health or a medical condition.