7 terrifying diseases you could have without knowing it

Could your heart be a ticking time bomb without you knowing? Probably.
Could your heart be a ticking time bomb without you knowing? Probably.

Conditions such as fever or pain are clear signs that there is something wrong with your body. Whether serious or not, physical symptoms tell us when we're sick, prompting us to seek rapid diagnosis and treatment. 

But what if you're harbouring a disease without realising it? It is not as farfetched as it may sound. Here are seven illnesses you could be suffering from without showing any symptoms:

1. Heart disease

There are several diseases linked to the heart. Heart disease can be hereditary, but it’s also something that can develop over time because of factors like unhealthy habits and ageing. Heart disease can be fatal, but it’s unfortunately not always easy to spot. Symptoms can be atypical and not severe enough to signify a problem. By the time a person experiences serious symptoms, the heart could already be significantly damaged.

Be vigilant: Have regular cholesterol and blood-pressure checks to identify any possible risk factors that could cause heart disease. Have a clear understanding of your family’s medical history and mention to your doctor if heart disease runs in your family.

2. Colorectal cancer

Colorectal cancer (cancer of the colon) is difficult to detect with a colonoscopy. It can take several years for an abnormal polyp in the digestive system to develop into cancer. According to, the survival rate for colon cancer is 90%, but only about four out of 10 colorectal cancers are found in time. When cancer has spread, survival rates are much lower. Symptoms usually start to manifest when the cancer has already spread. By then it may be too late for effective treatment.

Be vigilant: A healthy diet, weight and exercise can significantly lower your risk for colon cancer. Do not hesitate to contact your doctor when you experience a random change in appetite, bowel movements or any type of digestive problems.

woman visiting her doctor

3. Glaucoma

Glaucoma is a disorder where pressure builds up behind the eye. This can eventually lead to partial or complete loss of sight in the eye. It’s important to detect glaucoma early to avoid loss of sight. It has no symptoms or very subtle symptoms. The progression is so gradual that you may not recognise the progressive patchy loss of your peripheral field of vision. The central part of the vision is not affected until very late. Damage almost always goes unnoticed until it is too late.

Be vigilant: You can only detect glaucoma through regular eye tests. You should have your eyes tested regularly for glaucoma especially if you have a family member with glaucoma, if you have bad vision, or if you have had an injury to your eyes.

4. Huntington’s disease

Huntington’s disease is a genetic disorder that causes the degeneration of nerve cells in the brain. This disease can be present without any symptoms, but by the time symptoms appear, it develops quite rapidly.  In some cases, symptoms can start before the age of twenty in the form of learning disabilities and psychological problems. Huntington’s disease can be hard to diagnose.

Be vigilant: Prenatal testing is possible if you have any family member suffering from the disease and you are worried about the status of your unknown baby. To make a diagnosis, a doctor will also take a full medical and family history and do a clinical examination, involving physical and neurological evaluation.

Those who are at risk but do not yet have symptoms may choose to be genetically tested. Because there is no cure, and because such tests cannot predict the onset or severity of the disease, this decision should be carefully considered. 

5. Hypertension

Hypertension is not a disease as such, but a condition that can lead to illnesses such as heart disease and stroke. People are often unaware that they have high blood pressure and symptoms can be minimal. There is a reason why hypertension is often called “the silent killer”. High blood pressure develops over time.

Be vigilant: Have your blood pressure checked regularly. You can improve high blood pressure by making changes to your lifestyle.

6. Deep vein thrombosis

Deep vein thrombosis (also called pulmonary embolism or DVT) occurs when a clot forms in the deep, larger, lower veins of the legs. This condition occurs when the blood pools in your legs or if your blood is prone to clotting. About half of the people who experience DVT have no symptoms until the clot forms and interrupts circulation, which can be fatal.

Be vigilant: Look out for persistent pain and swelling in one leg and be vigilant when you are going through long periods of inactivity, such as long-haul flights or bed rest after an operation.

7. Chlamydia

This sexually transmitted disease is one of the most common STDs and can present without symptoms for a while – in fact, 80% of women with chlamydia are unaware that they have it. If it’s so common and can go unnoticed, why is it serious? The answer is that untreated chlamydia can cause a host of health complications including infertility, reactive arthritis and pelvic inflammatory disease (PID).

Be vigilant: Don’t have unprotected sex and get tested for chlamydia regularly, as chlamydia can be asymptomatic, especially in women. 

Image credits: iStock

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