What is the "Three Highs"? Definition, Diagnosis & Control Methods

The article has been reviewed by Dr. Lau Wai Ling, Head of Health Centre, St. Paul's Hospital

"Three Highs" is a common health issue among modern urban dwellers and is closely related to various chronic diseases. This article will comprehensively deconstruct the definitions, causes, symptoms, diagnoses, and improvement methods of the Three Highs, enabling you to prevent and effectively control them early on.

What are the Three Highs?

As the name implies, the Three Highs refer to three common chronic metabolic diseases: high blood pressure, high blood sugar, and high blood lipids. These three often occur together and influence each other, potentially causing serious harm to the body over time.

Blood Pressure (High Blood Pressure)

High blood pressure refers to arterial blood pressure that remains consistently above the normal range. In its early stages, high blood pressure often has no obvious symptoms but gradually damages vital organs such as the heart, brain, and kidneys. According to the latest guidelines from the Department of Health and international standards, an ideal blood pressure is generally below 120/80 mmHg. Adults with a sustained systolic pressure of ≥ 140 mmHg or a diastolic pressure of ≥ 90 mmHg measured at different times can be diagnosed with high blood pressure. When systolic pressure is between 120 to 139 mmHg or diastolic pressure is between 80 to 89 mmHg, it is classified as pre-high blood pressure¹. Due to the absence of noticeable symptoms, high blood pressure is often referred to as the "silent killer."

Blood Sugar (High Blood Sugar)

High blood sugar refers to an abnormal increase in the concentration of glucose in the blood, commonly seen in diabetes or prediabetes. According to the Hong Kong Diabetes Association, fasting blood sugar of ≥ 7.0 mmol/L or random blood sugar/2-hour post-oral glucose tolerance test blood sugar of ≥ 11.1 mmol/L, or glycated hemoglobin (HbA1c) of ≥ 6.5% may indicate diabetes. If fasting blood sugar is between 6.1 and 6.9 mmol/L, it falls under prediabetes².

Blood Lipids (High Blood Lipids)

High blood lipids refer to elevated levels of fats (cholesterol and triglycerides) in the blood. Cholesterol is an important substance for forming cell membranes and synthesizing hormones, but excessive amounts can accumulate in the walls of blood vessels. The generally recommended health standards for blood lipids are: total cholesterol < 5.2 mmol/L, low-density lipoprotein cholesterol < 2.6 mmol/L, high-density lipoprotein cholesterol for men ≥ 1.0 mmol/L, women ≥ 1.3 mmol/L, and triglycerides < 1.7 mmol/L². High blood lipids typically show no symptoms and need to be detected through blood tests.

Symptoms of the Three Highs

The "Three Highs" often do not present obvious symptoms in their early stages. As a result, many patients only realize they are affected when severe complications arise, such as stroke, heart disease, kidney failure, or vision impairment. Although these conditions may be hard to detect initially, you should remain vigilant and seek medical assistance if your body shows the following warning signs:

• Hypertension: Mostly asymptomatic. Some individuals may experience headaches (especially at the back of the head), dizziness, neck stiffness, palpitations, fatigue, or tinnitus.
  
  
• Hyperglycemia: Early symptoms include thirst, frequent urination, increased appetite, unexplained weight loss, easy fatigue, blurred vision, itchy skin, or slow healing of wounds.
  
  
• Hyperlipidemia: Typically asymptomatic as well. In rare severe cases, patients may develop yellow lipomas (cholesterol deposits) under the skin or on the eyelids.

Because these symptoms can be confused with other diseases or may not appear at all, regular health check-ups are the most important way to assess and manage the Three Highs.

Why Are There Issues with the "Three Highs"?

The formation of the "three highs" (high blood pressure, high blood sugar, and high blood lipids) is the result of a combination of various factors, including lifestyle habits, diet, and genetics. Understanding these causes can help us better prevent and control these conditions.

• Unhealthy Eating Habits: Diets high in salt, sugar, and fat are significant contributors to the three highs. Excessive salt intake can easily lead to high blood pressure, while consuming too much sugar and refined carbohydrates increases the burden on the pancreas, ultimately causing high blood sugar. Additionally, excessive intake of saturated and trans fats directly leads to high blood lipids.
  
  
• Lack of Exercise: Insufficient physical activity lowers metabolic rates and increases the risk of obesity and insulin resistance, thereby raising the incidence of the three highs.
  
  
• Obesity: Particularly central obesity (abdominal fat) is closely associated with insulin resistance, high blood pressure, and high blood lipids. Adipose tissue releases various inflammatory factors that affect the regulation of blood pressure, blood sugar, and blood lipids.
  
  
• Smoking and Alcohol Consumption: Smoking damages vascular endothelium and increases the risk of atherosclerosis; excessive alcohol consumption can lead to elevated blood pressure and triglyceride levels.
  
  
• Genetic Factors: If there is a family history of the three highs, the risk of developing these conditions is relatively higher. Genetic makeup can influence the body's ability to metabolize salt, sugar, and fat.
  
  
• Aging: As we age, blood vessels gradually age as well, insulin function may decline, and metabolism slows down, all of which increase the risk of the three highs.
  
  
• Chronic Stress: Prolonged mental stress can lead to hormonal changes in the body, affecting the stability of blood pressure, blood sugar, and blood lipids.

Who is Considered High-Risk for the "Three Highs"?

The Three Highs can affect anyone, but certain specific groups have a higher risk of developing these conditions:

• Obese or Overweight Individuals: Especially those with significant abdominal fat accumulation, who are more likely to experience insulin resistance, high blood pressure, and abnormal blood lipids.
  
  
• Inactive Individuals: A sedentary lifestyle can lower metabolism and increase the risk of disease.
  
  
• Individuals with a Family History of the Three Highs: Genetic factors play an important role in the development of these conditions.
  
  
• Long-Term Smokers or Excessive Drinkers: These harmful habits can directly damage cardiovascular health.
  
  
• Individuals with Unbalanced Diets: Those who consume excessive amounts of high-salt, high-sugar, high-fat, and high-cholesterol foods.
  
  
• Older Individuals: as age increases, bodily functions gradually decline, leading to reduced vascular elasticity and a higher risk of the Three Highs.
  
  
• Individuals Experiencing Long-Term Stress: Stress can affect the endocrine system, causing fluctuations in blood pressure, blood sugar, and blood lipids.
  
  
• Patients with Other Related Diseases: or example, those with sleep apnea, polycystic ovary syndrome, and other conditions.

If you find yourself in a high-risk group, be sure to actively improve your daily habits and discuss with your doctor to develop a suitable prevention and monitoring plan.

What Health Problems or Complications Can the Three Highs Cause?

The Three Highs are referred to as "silent killers" because if they are not effectively controlled over the long term, they can cause widespread and severe damage to various organs in the body, leading to a series of life-threatening complications.

Effects of High Blood Pressure

Long-term high blood pressure causes blood vessels to endure excessive pressure for extended periods, leading to thickening and hardening of the vessel walls, known as arteriosclerosis, which results in a loss of vascular elasticity. This condition significantly increases the risk of stroke, heart disease (such as heart failure or myocardial infarction), and kidney failure. Additionally, high blood pressure can lead to retinal damage, which, in severe cases, can result in blindness.

Risks of High Blood Sugar

Chronic high blood sugar can damage blood vessels and nerves throughout the body, greatly increasing the risk of diabetes and its various complications. These may include kidney disease, retinal damage, and even blindness, as well as neuropathy. Furthermore, high blood sugar can accelerate arteriosclerosis, significantly increasing the risk of cardiovascular diseases and strokes.

Dangers of High Blood Lipids

High blood lipids, particularly elevated levels of "bad cholesterol" (LDL-C) and triglycerides, can lead to the gradual accumulation of fat within the walls of blood vessels, forming atherosclerotic plaques. These plaques narrow the vessels, obstructing normal blood flow and greatly increasing the likelihood of coronary heart disease and peripheral vascular disease. Most seriously, these plaques can rupture, triggering blood clots that may ultimately lead to a myocardial infarction or stroke.

How to Determine / Test for the Three Highs?

Since the "three highs" (hypertension, hyperglycemia, and hyperlipidemia) often have no obvious symptoms in the early stages, the most effective and accurate way to assess them is through regular health check-ups. Here are the primary testing methods for the three highs:

Hypertension

To determine if one has hypertension, the main method is to measure the blood pressure in the arm using a sphygmomanometer. For accurate values, it is recommended to measure regularly at home or during each doctor's visit, and to take multiple measurements at different times to obtain an average. Generally, if an adult has a systolic blood pressure of ≥ 140 mmHg or a diastolic blood pressure of ≥ 90 mmHg measured at different times, they can be diagnosed with hypertension. If the systolic pressure is between 120 to 139 mmHg or the diastolic pressure is between 80 to 89 mmHg, this is classified as prehypertension¹. However, this is merely a reference standard; the final diagnosis should be based on the individual's specific situation as assessed by a doctor.

Hyperglycemia

Testing for hyperglycemia usually involves multiple blood tests. First, a fasting blood glucose test is conducted, requiring at least 8 hours of fasting before blood is drawn. If the value reaches or exceeds 7.0 mmol/L, it can be diagnosed as diabetes; values between 5.6 to 6.9 mmol/L indicate prediabetes².  Another method is the Oral Glucose Tolerance Test (OGTT), where blood is measured after fasting and then glucose water is consumed, with another blood draw 2 hours later. If the value reaches or exceeds 11.1 mmol/L, it is also diagnostic of diabetes². Additionally, the glycated hemoglobin (HbA1c) test reflects the average blood glucose level over the past 2 to 3 months without the need for fasting; a value of 6.5% or higher indicates diabetes. Lastly, if a random blood glucose measurement at any time reaches or exceeds 11.1 mmol/L, accompanied by related symptoms, a doctor can also make a diagnosis based on this.

Hyperlipidemia

To test for hyperlipidemia, a lipid panel is required, which typically involves fasting for 9 to 12 hours before the blood draw. This test analyzes multiple indicators in the blood to determine if lipid levels are healthy. Ideal values include: total cholesterol should be below 5.2 mmol/L³; low-density lipoprotein (LDL), known as "bad cholesterol," should ideally be below 2.6 mmol/L; high-density lipoprotein (HDL), known as "good cholesterol," should be at least 1.0 mmol/L for men and at least 1.3 mmol/L for women; finally, triglycerides should be below 1.7 mmol/L³.

How to Improve the Three Highs? What Dietary Changes

Should Be Considered?

Improving the issues related to the Three Highs not only requires medication under a doctor's guidance but, more importantly, involves lifestyle changes and dietary adjustments. These changes can help control current levels and prevent complications from occurring.

( Click the image to enlarge )

1. Healthy Eating Habits (Three High Diet)

To control the Three Highs, the key is to adjust dietary habits. Patients should consume more fruits, vegetables, whole grains, and lean meats to ensure a balanced diet. It is also essential to strictly control salt intake, limit processed foods and takeout to avoid raising blood pressure, and reduce sugary drinks and desserts, as excess sugar can affect blood sugar and lipids. When it comes to fat intake, avoid fatty meats and fried foods, and opt for foods rich in healthy fats, such as fish, avocados, and nuts. Additionally, foods high in cholesterol, like egg yolks, should be consumed in moderation. Lastly, it is advisable to use low-oil cooking methods, such as steaming, boiling, or baking, to reduce fat intake from the source.

The registered dietitian at St. Paul's Hospital provide individual nutritional consultations and dietary guidance to help you develop a personalized meal plan, effectively manage the Three Highs, and take an important step toward better health! Welcome to make an appointment and inquiry. 

2. Regular Exercise

To improve the Three Highs, it is important to develop a regular exercise habit. It is recommended to engage in at least 150 minutes of moderate-intensity aerobic exercise (such as brisk walking, jogging, or swimming) per week, or 75 minutes of high-intensity aerobic exercise, along with muscle-strengthening activities at least twice a week. These exercises can effectively lower blood pressure, improve insulin sensitivity to stabilize blood sugar, reduce triglycerides, and increase "good cholesterol," significantly aiding in weight management.

3. Maintain a Healthy Weight

Obesity is a major risk factor for the Three Highs. Even a weight loss of 5%-10% can significantly improve blood pressure, blood sugar, and lipid levels. Achieve and maintain an ideal weight through healthy eating and regular exercise.

4. Quit Smoking and Limit Alcohol

Quitting smoking and limiting alcohol intake are equally important. Smoking severely damages the cardiovascular system, making cessation one of the most effective measures to improve the Three Highs. Excessive alcohol consumption can raise blood pressure and triglycerides, placing a burden on the body. It is generally recommended that men limit alcohol intake to no more than two drinks per day, and women to no more than one drink.

 5. Manage Stress

Chronic stress can affect hormone levels, leading to fluctuations in blood pressure and blood sugar. Learning effective stress management techniques, such as exercise, meditation, yoga, deep breathing, pursuing hobbies, or talking with friends and family, can help reduce stress.

6. Ensure Adequate Sleep

Lack of sleep can affect insulin sensitivity and appetite-regulating hormones, increasing the risk of the Three Highs. Therefore, it is crucial to ensure 7-9 hours of quality sleep each night.

7. Regular Check-ups and Following Doctor's Advice

Even if symptoms are not obvious, regular check-ups are essential to monitor changes in blood pressure, blood sugar, and lipid levels. St. Paul's Hospital Health Centre  offers a variety of health check services for individuals of different ages. The professional medical team will provide appropriate treatment plans based on your health status. If you have been diagnosed with the Three Highs, strictly follow your doctor's instructions, take medications on time, and do not adjust dosages or stop taking medications without consulting your doctor. Work closely with your doctor and dietitian to create a personalized management plan. Through lifestyle improvements, the Three Highs can be effectively controlled. The key lies in consistent effort and proactive health management. For inquiry or consultation, please feel free to schedule an appointment with the Health Centre at St. Paul's Hospital. 

Frequently Asked Questions

Is the "Three Highs" Issue Common in Hong Kong?

The Three Highs are very common in Hong Kong. According to data from the Department of Health, the prevalence of high blood pressure, diabetes (high blood sugar), and high cholesterol (high blood lipids) among the population aged 15 to 84 is quite high and shows a trend of affecting younger individuals:

• High Blood Pressure: The prevalence rate is 29.5% (approximately 1 in 3 people)⁶.
  
  
• Diabetes (High Blood Sugar): The overall prevalence is 8.5% (11.1% for men; 6.1% for women)⁶.
  
  
• High Cholesterol (High Blood Lipids): The prevalence is as high as 51.9%, making it the most common issue among the Three Highs (1 in 2 people); in the 55-64 age group, the prevalence reaches 72.1%⁶.

From What Age Should One Start Regular Check-ups for the Three Highs?

It is generally recommended that adults start monitoring their blood pressure regularly from the age of 18. For blood sugar and blood lipids, individuals aged 35 and above should have at least one check-up per year. If there is a family history of the Three Highs or if one belongs to high-risk groups such as those who are obese or inactive, check-ups should start earlier, with increased frequency based on a doctor's advice.

How Can One Self-Check for the Three Highs?

High blood pressure can be measured at home using an electronic blood pressure monitor. It is advisable to purchase a validated device and follow the correct measurement steps. However, high blood sugar and high blood lipids cannot be accurately self-detected and require blood tests at medical facilities for confirmation. Nonetheless, you can pay attention to related symptoms, such as thirst, frequent urination, abnormal weight changes, dizziness, etc. If you suspect any issues, seek medical advice promptly.

If the Three Highs Are Well-Controlled, Is Medication Still Necessary?

Even if the indicators for the Three Highs reach ideal levels, most patients still need to continue taking medication under a doctor's guidance. This is because the Three Highs are long-term chronic conditions, and stopping medication can easily lead to a rebound in indicators, increasing the risk of heart disease, stroke, and other complications. Only after a thorough assessment of your health status and risks by a doctor can there be a possibility of gradually reducing medication. Never stop or reduce medication on your own, as this may worsen your condition. Regular follow-ups and monitoring are crucial for effectively managing the Three Highs.

References:

1. Centre for Health Protection, Hypertension
2. Smart Patient, Hospital Authority, Diabetes Mellitus
3. 香港衞生署衞生防護中心, 預防血液中的膽固醇水平過高
4. 香港衞生署衞生防護中心, 高血壓：主要事實及預防行動
5. Department of Health, Hypertension: Key Facts and Preventive Actions
6. DH releases Population Health Survey Report (Part II)