Hawker food, desk jobs and long workdays: when should you consider a colonoscopy?

For many people living in Singapore, colonoscopy sits somewhere between “important” and “not yet.” We know it is recommended. We know someone who has had one. We assume we will get to it eventually.

In clinic, I often hear two versions of the same sentence:
“I feel fine.”
“I’ll do it next year.”

As a gastroenterologist, I understand the hesitation. Colonoscopy is not a pleasant word. It feels invasive. It feels like something meant for an older version of ourselves.

But the reality in Singapore is straightforward. Colorectal cancer remains one of the most common cancers locally. According to the Singapore Cancer Registry, it is consistently among the top cancers diagnosed in both men and women. The majority of cases occur in adults aged 50 and above.

Age remains the strongest risk factor.

Globally, there has been growing attention on rising colorectal cancer rates in younger adults. That conversation is important. However, in Singapore, the highest incidence remains in those over 50.

The more pressing issue is not that everyone in their 30s needs a colonoscopy. It is that many eligible adults in their 50s and 60s are still not screened.

Early colorectal cancer usually causes no symptoms. By the time bleeding, pain or a persistent change in bowel habits appears, the disease may already be more advanced. Screening exists precisely because symptoms are often a late sign.

Living in Singapore often means long hours at a desk, limited time for exercise and frequent dining out. Low fibre intake, obesity and sedentary behaviour are recognised risk factors. Over time, these patterns may contribute to colorectal cancer risk, particularly when combined with age.

However, lifestyle alone does not determine who develops cancer. Even individuals who exercise regularly and eat well are not exempt once they cross 50. Screening is recommended because risk increases with age, regardless of how healthy you feel.

Many screening tests detect disease. Colonoscopy can prevent it.

Most colorectal cancers develop from polyps over several years. During a colonoscopy, these polyps can be identified and removed before they become cancerous. That is a crucial distinction.

From a specialist’s perspective, colonoscopy is one of the most effective preventive tools we have. Screening has been shown to reduce both colorectal cancer incidence and mortality because it interrupts the disease process early.

This is where a conversation with your GP becomes important.

In Singapore, colonoscopy typically requires a referral. Your GP will assess your age, personal medical history, family history and any symptoms. Based on this evaluation, they may recommend screening and refer you to a gastroenterologist or colorectal surgeon for further assessment and the procedure.

If you are 50 or older and at average risk, screening should be discussed even if you feel entirely well. If you are younger but have a first-degree relative with colorectal cancer, a history of polyps, chronic inflammatory bowel disease or persistent symptoms such as rectal bleeding, earlier evaluation may be advised.

In some private settings, it may be possible to book a colonoscopy directly without a prior referral. However, even in those cases, a medical assessment beforehand is important to ensure the procedure is appropriate for you.

The key point is this: colonoscopy is not a test to self-prescribe casually. It is part of a broader assessment of risk and screening strategy.

Modern colonoscopy in Singapore is typically performed under sedation in a day surgery setting. Patients are comfortable during the procedure and usually return home the same day. Patients frequently say they are so comfortably asleep that they don't remember the procedure at all. Patients usually resume their usual work or activities within a very short time post colonoscopy.

The fear of the procedure often outweighs the reality of it.

If you are 50 or older and living in Singapore, it is reasonable to review your colorectal cancer screening status with your GP, even if you have no symptoms. Screening recommendations are based on age and risk, not on how you feel day to day.

If you are younger but have rectal bleeding, a sustained change in bowel habits, unexplained weight loss, or a first-degree relative diagnosed with colorectal cancer, you should seek medical advice rather than monitor the symptoms on your own.

Under Healthier SG, colorectal screening is available at CHAS GP clinics at a subsidised fee, including HMI OneCare Clinics. Your GP can assess your individual risk and advise whether a test is appropriate, or whether referral for further evaluation such as colonoscopy is indicated.

Colonoscopy is not necessary for everyone at the same time. The appropriate timing depends on your age, medical history and risk factors. The most important step is ensuring that screening decisions are made in consultation with a doctor, rather than delayed indefinitely.