Understanding Lifestyle Related Diseases

Depression

We all go through ups and downs in our mood. Feeling ‘sad ‘or having a ‘low’ mood from time to time as a reaction to stressful events is a normal part of life. However, this cannot be considered as depression. It is important to understand that depression is different from the occasional feeling of sadness, which tends to pass rather quickly. Depression is much more than just sadness. It is a clinical condition, which if left untreated can lead to some serious complications, including suicidal death.  It is important to remember that, no matter how hopeless you feel, it is possible to get over depression. But first, let’s try to understand what depression really is? Learning about the symptoms, causes and risk factors is the first step towards identifying if you or someone around you is suffering from depression.  


What Is Depression? 

Depression is a serious mental disorder, which shows both mental as well as physical symptoms. People who suffer depression often appear sad and show irritable mood that is of a very high intensity. A person suffering from depression also shows specific changes in bodily functions such as crying spells, body aches, low energy or libido, as well as problems with eating, and weight.  


How Is Depression Different From The Normal Emotion That We Feel?  · 

We all feel sad as a normal reaction to life’s struggles, and disappointments. Many people explain these kinds of feelings as “depression.” However, these feelings cannot be termed as depression, because they fade away and disappear usually in a few days. Depression is a chronic illness that often requires long-term treatment, like diabetes or high blood pressure. Depression is not just sadness. Some people who suffer depression don't even feel sad; instead they may feel lifeless and empty or just irritated. Men in particular may even feel angry, aggressive, and restless. Depression means feeling of sadness that does not go away and  interferes with day-to-day life, ability to work, study, eat, sleep, and have fun. Depression can be accompanied with feelings of helplessness, hopelessness, and worthlessness and these can be intense. People who are depressed may stop participating in certain everyday activities altogether. They tend to isolate themselves from family and friends. They may stop enjoying the things that they used to enjoy. Some depressed individuals may even have thoughts of committing suicide.


Risk Factors for Depression In Women  

Women are nearly twice as likely as men to have depression. The causes of such higher rates of depression appear to be as follows: 

  • Sociocultural Factors  Stress from work, family responsibilities, and childcare can play a role in triggering depression in women. Also, women who live in poverty and have a history of sexual abuse are at a higher risk of developing depression.                          
  • Hormonal changes  Mainly during puberty, the hormonal changes occurring in the body, put girls at higher risk of depression compared to boys of same age. 
  • Menstruation  Many women experience mood changes around the time of menstruation. Some women suffer from a condition called premenstrual dysphoric disorder (PMDD). PMDD is a specific psychiatric syndrome that includes severe depression, irritability, and tension before menstruation.  
  • Perimenopause and Menopause Depression is common in women when they transition to menopause. This occurs due to fluctuating hormones in this phase.      

Risk Factors for Depression In Men 

Depression in men is not as common as in women.Although the exact reason for this disparity is unknown, it is well established that hormonal changes in women increase their risk of depression.However, rates of suicide are three to four times higher in men than women. Since, depression is considered to play a major role in most suicides, it clearly affects men in significant ways.Depression in men is mainly caused due to the following factors:

  • Increased stress
  • Impulsive behavior
  • History of alcohol or substance abuse
  • Family history of depression, alcohol abuse, or suicide

Risk Factors for Depression In Children and Adolescents

Depression can affect children of any age. Adolescents are at higher risk of developing depression. Depression in children or adolescents is caused due to following factors:

  • Parents with depression
  • Negative experiences and exposure to stress, neglect, or abuse at younger age
  • Certain physical illnesses
  • In adolescents, a feeling of being separated from parents

Risk Factors for Depression In Elderly

Some difficult changes in life, such as loss of spouse, loss of independence, and health problems can lead to depression. Depression in older adults is associated with poor health, high mortality rate, and an increased risk of suicide.  


  References

1. Mood Disorders. http://medicalcenter.osu.edu/patientcare/healthcare_services/mental_health/mental_health_about/mood/Pages/index.aspx. Accessed April 23, 2013. 

2.  Cash RE, Cowan K. Mood Disorders: What Parents and Teachers Should Know. Cowan NASP Communiqué, 2006; 35 (3). 

3.  Psychology 101. Motivation and Emotion. Available online: http://allpsych.com/psychology101/emotion.html. Accessed April 23, 2013. 

4. Gould J. Emotion—What is it? Available online: http://uwf.edu/jgould/Emotion%20What%20is%20it.pdf. Accessed April 23, 2013. 

5. Amado-Boccara I, Donnet D, Olié JP. [The concept of mood in psychology]. Encephale. 1993; 19(2):117-122. 

6. Rottenberg J. Mood and Emotion in Major Depression. Current directions in psychological science. 2005; 14 (3): 167-170. Available online: http://uweb.cas.usf.edu/mood/docs/cd.pdf. Accessed April 23, 2013 

7.  Neurotransmitters. Chapter 2: Biopsychology.  Section 2: Neurotransmitters. http://allpsych.com/psychology101/neurotransmitters.html. Accessed April 23, 2013 

8. Boeree CG. Neurotransmitters. http://webspace.ship.edu/cgboer/genpsyneurotransmitters.html. Accessed April 25, 2013 

9. Khaleghipour S, Masjedi M, Ahade H et al. Morning and nocturnal serum melatonin rhythm levels in patients with major depressive disorder: an analytical cross-sectional study. Sao Paulo Med J. 2012; 130(3):167-172. 

10. What Is Endorphin Deficiency?http://www.wisegeek.org/what-is-endorphin-deficiency.htm. Accessed April 25, 2013 

11. Depression Symptoms & Warning Signs. http://www.helpguide.org/mental/depression_signs_types_diagnosis_treatment.htm. Accessed April 23, 2013 

12. Depression. http://www.medicinenet.com/depression/article.htm#toca. Accessed April 23, 2013 

13. Depression. Review. http://familydoctor.org/familydoctor/en/diseases-conditions/depression.html Accessed April 26, 2013 

14. Understanding depression and effective treatment. http://www.apa.org/helpcenter/understanding-depression.aspx. Accessed April 23, 2013 

15. Depression.  http://www.who.int/mediacentre/factsheets/fs369/en/. Accessed April 23, 2013 19. Prevalence of Current Depression* Among Persons Aged ≥12 Years, by Age Group and Sex — United States, National Health and Nutrition Examination Survey, 2007–2010. Morbidity and Mortality Weekly Report (MMWR). 2012; 60(51, 52). http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6051a7.htm.  Accessed May 3, 2013. 

16. Causes of Depression. http://www.nimh.nih.gov/health/publications/men-and-depression/causes-of-depression.shtml. Accessed April 23, 2013. 

17. Depression - Risk Factors. http://www.umm.edu/patiented/articles/what_risk_factors_depression_000008_3.htm. Accessed April 23, 2013. 

18. Symptoms of depression. Available online: http://www.nhs.uk/Conditions/Depression/Pages/Symptoms.aspx. Accessed April 23, 2013.  

19. Depression – Diagnosis. http://www.umm.edu/patiented/articles/how_depression_diagnosed_000008_5.htm. Accessed April 23, 2013.

Diabetes

What is diabetes? 

Diabetes is a disorder in which the body is unable to breakdown glucose (sugar) into energy that is required by your body cells for survival. The food you eat is converted into glucose, which is further converted into energy by a hormone known as “insulin.” It means if a person has diabetes there is some problem with insulin production or its utilization.   In diabetes, whether your body is not making enough insulin or not able to use it properly, glucose levels are going to increase in your blood. This leads to a condition known as hyperglycemia. (hyper ~ high, glycemia~ glucose).   


Role of Insulin 

Insulin is a hormone produced by beta cells in the pancreas (leaf shaped organ located behind the stomach). When you eat food, it is converted into glucose, which travels in your bloodstream (to gain entry into cells and to produce energy). Sufficient amount of insulin is required for the glucose to enter into your body cells. Without adequate amount of insulin, glucose levels increase in the bloodstream, leading to a condition known as diabetes.   


Pre-diabetes 

Pre-diabetes is a condition that comes before type 2 diabetes. Blood glucose levels are higher than normal but aren’t high enough to be called diabetes.   


What are the symptoms of diabetes? 

A large majority of people with diabetes remain undiagnosed due to lack of awareness and recognition of the symptoms. Many of the diabetes symptoms appear during later stages of the disease. Therefore if you feel any of the following symptoms, consult your physician immediately.    

  • Increased thirst and frequent urination. As excess glucose builds up in your bloodstream, water is pulled out from the tissues. This may make you unusually thirsty. As a result, you may drink and urinate more than usual.
  • Increased hunger. Without enough insulin to move glucose into your cells, your muscles and organs become depleted of energy. This triggers hunger. Increased cravings or hunger can be a sign of type 2 diabetes.
  • Weight loss. The cells in your body are deprived of energy.Due to the lack of glucose in the body cells, other body fuels such as fat is used to produce energy, and this results in loss of weight.
  • Fatigue. If your body cells are not getting enough glucose, they are deprived of energy, which results in fatigue.
  • Blurred vision. High blood glucose leads to swelling of eye lens and this may affect your vision.
  • Slow-healing sores or frequent infections. Diabetes affects your ability to heal and resist infections.   


What is HbA1C test? 

The hemoglobin (Hb) A1C test determines how your metabolism is working. A1C levels between 5.7% and 6.4% indicate that you have pre-diabetes.  


What are the different types of diabetes? 

Defect in insulin leads to either type 1 diabetes or type 2 diabetes.   

  • If your body is not making enough insulin, it leads to a condition called type 1 diabetes.
  • If your body is making insulin but not able to use it correctly, it leads to condition called type 2 diabetes.
  • Many women develop high blood glucose levels during their pregnancy. This is known as gestational diabetes.   

What is Type 1 diabetes? 

Type 1 diabetes is an autoimmune disorder in which your body’s immune system attacks the insulin producing beta cells in the pancreas. Due to this, your pancreas are not able to produce sufficient amount of insulin that is required to breakdown glucose. This leads to increase in glucose levels in your blood, which is known as hyperglycemia. Scientists believe that both genetic and environmental factors are responsible for causing type 1 diabetes. Type 1 diabetes happens most often in children and young adults, but can appear at any age. Type 1 diabetes can be treated by supplying your body with external insulin. Multiple doses of insulin may be required through the day to meet the body’s demands. Insulin can be administered either through injections, pens, or continuous infusion pumps.Type 1 diabetes also requires that you closely monitor your blood glucose levels.    


What is Type 2 diabetes? 

Type 2 diabetes is a disorder in which your body is not able to produce enough insulin or the cells fail to sense the presence of insulin. Although in response to this your pancreas may produce more insulin, eventually your pancreas become exhausted and stop producing insulin completely. Type 2 diabetes is the most common form of diabetes and is generally more common in middle aged and older people.    


What is Gestational diabetes? 

Gestational diabetes is a form of diabetes in which the blood glucose levels rise during pregnancy. When you are pregnant, your body requires higher amount of insulin to maintain normal blood glucose levels. When your body is not able to make or use all of the insulin it needs, glucose is barred from entering the body cells and can’t be changed to energy.   


Diabetes and Heart Disease 

If you have diabetes then you are at a greater risk of having a heart attack and heart failure. Heart is the major organ of your body. The main function of the heart is to pump blood to every part of the body and deliver energy to each cell. High blood glucose levels can lead to increased deposits of fatty materials in the walls of blood vessels. Due to this:  

  • Blood cannot flow properly and increases the risk of clogging and hardening of blood vessels (known as atherosclerosis).
  • Blood supply decreases as per the demand by your heart, which results in heart attack.
  • The heart muscles are damaged causing irregular heartbeats; therefore, your heart is not able to pump the blood properly (with every heart beat, blood is pumped out of your heart). This eventually results in heart      failure.
  • You are at a greater risk of peripheral artery disease (PAD) i.e. narrowing of the peripheral (outside the heart) arteries, commonly the vessels of the pelvis and legs. In PAD, the blood supply to your legs and feet decreases and you may experience numbness, tingling, coldness, or pain in legs while walking. In addition, PAD leads to slow healing of sores or infection in feet and legs. PAD is also known to increase the      risk of heart attack and stroke. 

Diabetes and Stroke 

If you have diabetes then you are at a greater risk of having stroke. In stroke, blood supply to the brain is cut off because of fatty material deposit or formation of blood clots in blood vessels in the brain or neck. Due to the lack of blood supply, brain cells don’t receive enough oxygen and ultimately die. You may also be at an increased risk of Transient Ischemic Attack (TIA)/ Mini-Stroke, which occurs for a short duration in which the blood supply to the brain is blocked temporarily. It results in weakness or numbness of one side of the body, difficulty in balancing, loss of speech, double vision or severe headache. Generally, these symptoms get resolved quickly; if not then TIA converts into stroke i.e. permanent damage to the affected part of the brain.


References:    

The following sources were used as a reference for creating this content in this section.   

1. Your guide to Diabetes: Type 1 and Type 2. National Institute of Diabetes and Digestive and Kidney Diseases. http://diabetes.niddk.nih.gov/dm/pubs/type1and2/index.htm. Referred 1 Dec. 12 

2. Diabetes and Pregnancy. National Institute of Diabetes and Digestive and Kidney Diseases. http://www.nlm.nih.gov/medlineplus/diabetesandpregnancy.html. Referred 4 Dec. 12 

3. Gestational Diabetes: A Guide for Pregnant Women. Agency for Health Care Research and Quality. AHRQ Pub. No. 09-EHC014-August 2009 

4. American Diabetes Association. http://www.diabetes.org/diabetes-basics/gestational/what-is-gestational-diabetes.html. Referred 4 Dec. 12 

5. Gestational Diabetes. The American College of Obstetricians and Gynecologists. Referred 4 Dec. 12 

6. American Diabetes Association. http://www.diabetes.org. Referred 10 Jan. 13 

7. Eisenbarth GS, Polonsky KS, Buse JB. Type 1 Diabetes Mellitus. In: Kronenberg HM, Melmed S, Polonsky KS, Larsen PR. Kronenberg: Williams Textbook of Endocrinology. 11th ed. Philadelphia, Pa: Saunders Elsevier; 2008:chap 31. Referred 1 Dec. 12 

8. Åkerblom HK, Knip M: Putative environmental factors in type 1 diabetes. Diabetes Metab Rev14 :31 –67,1998 Medline 

9. Peng H, Hagopian W: Environmental factors in the development of Type 1 diabetes: Rev EndocrMetabDisord. 2006 Sep;7(3):149-62.  

Heart Disease

Heart is a critical and one of the most important organs of the body and our lifestyle can have a huge impact on its condition. There are several forms of heart disease, but the two most common and to some extent modifiable are - high cholesterol and high blood pressure.


High Cholesterol


Cholesterol

Cholesterol (chole- bile and stereos- solid) is a type of lipid (fat) in your blood.It is vital for the body as it is required to build and maintain cell membranes and acts as a precursor for the biosynthesis of steroid hormones, bile acids, and vitamin D.  
 

Sources of Cholesterol  
Cholesterol comes from two sources:

  • Your body: Your liver and other cells in your body make about 75 percent of blood cholesterol.
  • Food: The remaining 25 percent comes from the food you eat (known as dietary cholesterol). 

Cholesterol is mostly found in animal products. Main dietary sources of cholesterol include cheese, egg yolks, beef, pork, poultry, fish, and shrimp. Human breast milk also contains significant quantities of cholesterol.  


Cholesterol and Lipoproteins Cholesterol being a type of lipid (fat) is insoluble in water and therefore, it is incapable of dissolving in blood (which is mostly water). To be carried in the blood, cholesterol combines with specific proteins to form a substance known as a lipoprotein. There are various kinds of lipoproteins in the body that carry cholesterol:

  • LDL (Low-density lipoproteins) cholesterol carries cholesterol from the liver to cells of the body. It is also known as bad cholesterol’ as it is the main source of cholesterol buildup and blockage in the arteries. An lDL-cholesterol level of less than 100 mg/dL is considered optimal and has a very low risk for Coronary heart diseases (CHD). LDL levels between 100-129 mg/dL puts you at a higher risk of developing atherogenesis and may accelerate if your LDL levels exceed more than 190mg/dL.
  • HDL (High-density lipoproteins) cholesterol carries cholesterol away from the arteries and back to the liver, where it's removed from your body. It is also known as good cholesterol’ as it removes excess cholesterol from an arterial plaque, slowing its build-up and protects against heart attack. That’s the reason why high levels of HDL cholesterol (more than 60mg/dL) are believed to have beneficial effects in protecting against heart attack. On the other hand, low levels of HDL cholesterol (less than 40 mg/dL for men and less than 50mg/dL for women) may increase your risk of heart disease.
  • Very low density lipoprotein (VLDL) cholesterol: They are triglyceride-rich lipoproteins that enable cholesterol to move within the water-based solution of the bloodstream. Some forms of VLDL appear to promote plaque buildup (atherosclerosis), similar to LDL (bad) cholesterol.
  • Chylomicrons: They are triglyceride-rich lipoproteins and are formed in the intestine from dietary fat and appear in the blood after a fat-containing meal and probably contribute to some extent in plaque formation.  

Triglycerides

Triglycerides are a kind of fat found in your blood and fat tissues. Triglycerides are not cholesterol, but are commonly measured along with cholesterol. Often, high triglycerides occur along with high total cholesterol, including high LDL (bad) cholesterol and low HDL (good) cholesterol. Triglycerides that are rich in lipoproteins,[known as Triglyceride Rich Lipoproteins (TGRLP)] are of two types: Very Low Density Lipoproteins (VLDL) and Intermediate Density Lipoproteins (IDL). VLDL transports triglycerides to the adipose tissue and muscles. The triglycerides in VLDL are removed from the capillaries by the enzyme lipoprotein lipase, and the VLDL returns to the circulation as a smaller particle with a new name, intermediate-density lipoprotein (IDL). VLDL and IDL are cholesterol- enriched particles and have many of the properties of LDL and contribute towards hardening and narrowing of your arteries. This puts you at risk of having a heart attack or stroke. Elevated triglycerides are generally caused due physical inactivity, cigarette smoking, excess alcohol consumption, and a diet very high in carbohydrates (60 percent of total calories or more). However, some diseases such as, diabetes, obesity, or kidney failure can also cause high triglycerides. 


Importance of Cholesterol/ Complications of High Cholesterol

Your blood cholesterol level is directly related to various heart diseases. High levels of cholesterol in the blood can increase your risk of heart attack. When too much LDL (bad) cholesterol circulates in the blood, it can slowly build up in the inner walls of the arteries that feed the heart and brain. Together with other substances, it can form plaque, a thick, hard deposit that can narrow the arteries and make them less flexible. This condition is known as “atherosclerosis”.  Plaque (atherosclerosis) makes the arteries narrow, which causes stress on other organs, such as the heart and the kidneys because of reduced blood flow. Many times, the plaque ruptures (breaks) resulting in formation of a clot. If a clot blocks a narrowed artery, it may result into a:

  • Heart attack(if blood supply to heart is restricted) or
  • Stroke(if blood supply to brain is restricted). 

Risk Factors

  • Sedentary Lifestyle: Exercise plays a vital role in increasing your body’s HDL levels and decreasing LDL levels. People who do not exercise at a regular basis and spend most of their time sitting/lying down can have significantly higher levels of LDL (bad cholesterol) and lower levels of HDL (good cholesterol).
  • Smoking: Cigarette smoking is one of the major risk factors for heart disease. It damages the thin lining of blood vessels making it more prone to accumulation of fatty deposits.
  • Family history of heart disease: If your parent or siblings have any of the heart disease before age 55, then you are at a greater risk of having high cholesterol levels.
  • Obesity: If you are overweight/ obese, then you are more likely to have higher LDL and lower HDL levels as compared to people who are of normal weight.
  • Nutrition: Some foods that are rich in cholesterol, such as seafood (shrimp, crawlfish or crayfish) red meat, some pies, sausages, hard cheese, lard, pastry, increase your cholesterol levels to a greater extent. 

References:

1. Cholesterol at the US National Library of Medicine Medical Subject Headings(MeSH). http://www.nlm.nih.gov/mesh/. Accessed April 25, 2013. 

2.  Hanukoglu I (Dec 1992). "Steroidogenic enzymes: structure, function, and role in regulation of steroid hormone biosynthesis." J Steroid Biochem Mol Biol 43 (8): 779–804 

3. Jensen RG et al. Lipids of human milk and infant formulas: a review. Am J ClinNutr 31 (6): 990–1016.  

4. Triglycerides. http://www.heart.org/HEARTORG/GettingHealthy/NutritionCenter/Triglycerides_UCM_306029_Article.jsp. Accessed April 26, 2013. 

5. Huffman KM, et al. Exercise effects on lipids in persons with varying dietary patterns - does diet matter if they exercise? American Heart Journal. 2012;164:117.  

6. Chapman MJ, et al. Triglyceride-rich lipoproteins and high-density lipoprotein cholesterol in patients at high risk of cardiovascular disease: Evidence and guidance for management. European Heart Journal. 2011;32:1345. 

7. What is cholesterol? National Heart, Lung, and Blood Institute. http://www.nhlbi.nih.gov/health/health-topics/topics/hbc/. Accessed April 24, 2012. 

8. About Cholesterol. http://www.heart.org/HEARTORG/Conditions/Cholesterol/Cholesterol_UCM_001089_SubHomePage.jsp. Accessed April 24, 2013. 


High Blood Pressure


What is High Blood Pressure/ Hypertension?

High blood pressure (also known as hypertension) is a chronic medical condition in which the blood pressure of the arteries gets elevated. When your heart beats, it pumps blood into your body to provide energy and oxygen it needs. As the blood flows, it pushes against the sides of the blood vessels and this pressure is known as blood pressure. If your blood pressure is higher than normal, it puts extra burden on your arteries (and your heart), which may lead to heart attack and stroke. 


Symptoms of Hypertension 

Hypertension is a silent disease and most of the time there are no symptoms. However, there are warning signs, which may appear long before an actual hypertensive crisis.  Following are the symptoms of a hypertensive crisis:

  • Bleeding of nose
  • Headache or blurred vision
  • Loss of consciousness
  • Severe chest pain and anxiety
  • Vertigo
  • Vomiting

If not treated well on time, hypertensive crisis can cause serious damage to your important body organs. 


Causes of High Blood Pressure

High blood pressure (hypertension) is classified as:

  • Primary hypertension: It is also known as essential hypertension or idiopathic hypertension. It is the most common type of hypertension with no identifiable medical cause of high blood pressure.
  • Secondary hypertension: It is caused by an underlying identifiable medical cause, i.e. by any other medical condition or medication. Various conditions that can lead to secondary hypertension are:
    • Atherosclerosis
    • Cancer
    • Certain medications such as birth control pills, corticosteroids, etc.
    • Cocaine use
    • Consumption of alcohol
    • Diabetes
    • Endocrine disorders such as hyperthyroidism, hypothyroidism − High levels of salt intake
    • Kidney damage   

Risk factors

You are at a higher risk of having high blood pressure if you have any of the following:

  • Age: older than 55 years for men, 65 years for women
  • Diabetes
  • Elevated LDL (or total) cholesterol, or low HDL cholesterol
  • Ethnicity(More common in Blacks)
  • Family history of high blood pressure
  • Obesity (BMI ≥30 kg/m2)
  • Physical inactivity
  • Tobacco usage (cigarettes) 

Possible Complications

When blood pressure is too high, it places an excessive burden on your arteries, which can damage your blood vessels as well as organs of your body. Uncontrolled blood pressure can lead to:

  • Life-threatening bleeding from the aorta (a large blood vessel that supplies blood to the abdomen, pelvis, and legs)
  • Kidney damage
  • Heart attack and stroke
  • Vision loss
  • Angina
  • Memory loss 


References 

1. CDC. Vital signs: prevalence, treatment, and control of hypertension. United States, 1999-2002 and 2005-2008. MMWR 2011;60(4):103–8. 

2. World Health Report 2002: Reducing risks, promoting healthy life. Geneva, Switzerland: World Health Organization. 2002. http://www.who.int/whr/2002/. 

3. Thomas L. Managing hypertensive emergencies in the ED. Can Fam Physician. 2011; 57 (10): 1137–97. 

4. Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7).Rockville, Md. National Heart, Lung, and Blood Institute, US Department of Health and Human Services; August 2004. National Institutes of Health Publication No. 04-5230. 

5. Wolff T and Miller T. Evidence for the reaffirmation of the U.S. Preventive Services Task Force recommendation on screening for high blood pressure. Ann Intern Med. 2007;147:787-791. 

6. Keenan NL and Rosendorf KA. Prevalence of hypertension and controlled hypertension—United States, 2005-2008. MMWR. 2011;60 Suppl:94-7.    


For additional reading, please go to http://www.heart.org/HEARTORG/Support/What-is-Cardiovascular-Disease_UCM_301852_Article.jsp#.WevwAxNSzOS

Obesity

According to the world health organization (WHO) report, overweight and obesity are the fifth leading threat to worldwide deaths. At least 2.8 million adults die each year as a result of being overweight or obese. Currently more than one billion adults are overweight and at least 300 million of them are clinically obese. Globally burden is increasing day by day.   Obesity Obesity is defined as excessive accumulation of body fat, which further increases the risk of chronic diseases, such as type 2 diabetes, heart disease, stroke, hypertension, musculoskeletal disorders, and some cancers. For measuring total body fat, The National Heart, Lung, and Blood Institute (NHLBI) guidelines recommend: 

  • Body Mass Index (BMI)
  • Individual’s waist circumference
  • Other diseases related with obesity i.e. high blood pressure or physical inactivity   

Body Mass Index (BMI) 

BMI estimates total body fat based on your height and weight. To calculate your BMI, divide your weight in kilograms by the square of your height in meters (kg/m2) or you can either use the BMI table or BMI calculator to estimate your body fat. The following indicates your weight status based on your BMI:

  • If BMI (kg/m2) is <18.5, you are Underweight and need to gain weight
  • If BMI (kg/m2) is 18.5-24.9, your weight is perfect. Maintain it
  • If BMI (kg/m2) is 25.0-29.9, you are Overweight; don’t gain weight, try to lose weight
  • If BMI (kg/m2) is 30.0-34.0, you are Obese; consult your doctor to lose weight

Limitations of BMI

Although BMI estimates the body fat, it has some limitations:

  • Athletes are more muscular but they don’t have excess body fat. As muscles always weigh heavier than fat, BMI test overestimates body fat in athletes, i.e. higher BMI although they have low body fat.
  • It may underestimate body fat in old age people.   

Waist Circumference Measurement  

According to the ‘Evidence Report’ by NHLBI, waist circumference is directly linked to the abdominal fat, which is an indicator of obesity-related diseases. If you have more fat around your waist, then you are at a higher risk of obesity-related heart diseases, diabetes, and dementia. According to a study, increase in abdominal fat cells result in the over-production of amyloid precursor protein (APP) which plays a vital role in learning and memory. The accumulation of APP in brain leads to damage of brain cells which in turn causes dementia. The risk increases with waist measurement.

  • Greater than 35 inches (88 cm) for women
  • Greater than 40 inches (102 cm) for men

If there are two people who have higher but same BMI, the one with a greater waist circumference has a greater likelihood of having health problems related to obesity.


Health Risks of Overweight and Obesity


Abnormal cholesterol levels

Cholesterol is type of a lipid (fat) in your blood. There are two main types of cholesterol. One is “bad cholesterol” and other is “good cholesterol”. Bad cholesterol, known as low density lipoprotein cholesterol or simply LDL cholesterol, is the main source of cholesterol buildup and blockage in the arteries. Good cholesterol, known as high density lipoprotein cholesterol or simply HDL cholesterol, carries cholesterol away from the arteries and back to the liver, where it's removed from your body. Triglycerides are also a type of fat having properties of LDL and contribute to hardening and narrowing of your arteries. People who are overweight and obese tend to have unhealthy diet (high in saturated and trans fats) and low physical activity. This results in high LDL, high triglycerides, and low HDL levels.    


Cancer 

People who are obese are at a higher risk of breast, colon, endometrium (lining of uterus), gallbladder and many other types of cancer. There are several proposed mechanisms, which explain the association of obesity and increased risk of certain cancers: 

  • Fat tissue produces excessive estrogen, which increases the risk of breast, endometrial, and other types of cancer.
  • People who are overweight or obese have higher levels of insulin and insulin-like growth factor-1 (IGF-1) in their blood, which may promote the development of certain tumors.    

Coronary Heart Diseases 

Overweight and obesity is a major risk factor for coronary heart disease. Heart is the major organ of your body. The main function of the heart is to pump blood to every part of the body and deliver energy to each cell. If you are overweight or obese, it can lead to increased deposits of fatty materials in the walls of blood vessels. Due to this:

  • Blood cannot flow properly, which increases the risk of clogging and hardening of blood vessels (known as atherosclerosis).
  • Blood supply decreased as per the demand by your heart, which results in heart attack.
  • The heart muscles are damaged, causing irregular heartbeats; therefore, your heart is not able to pump the blood properly (with every heart beat, blood is pumped out of your heart). This eventually results in heart failure.   

Gall stones

The liquid present in the bile in the gallbladder helps the body to digest fats. If the composition of the gallbladder liquid changes, i.e. higher concentration of cholesterol, bile salts, or bilirubin; it hardens and gallstones are formed. If these gallstones are left untreated, it can be fatal as gallstones passing through the bile duct aggravate inflammation in the pancreas, leading to gallstones pancreatitis. According to a clinical study in people who are overweight and obese, body tissues are flooded with fatty acids and more cholesterol is produced than the liver can process.   


Impaired glucose tolerance (Pre-diabetes) and Type 2 diabetes 

Diabetes is a disorder in which the body is unable to breakdown glucose (sugar) into energy that is required by your body cells for survival. The food you eat is converted into glucose, which is further converted into energy by a hormone known as “insulin.” In type 2 diabetes, your body is not able to produce enough insulin or the cells fail to sense the presence of insulin. Research has confirmed that overweight and obesity reduces insulin’s ability to control blood glucose. In response, your body starts producing more insulin in an attempt to bring the blood glucose levels to normal. With the passage of time, your body suffers exhaustion of producing excess insulin and is therefore unable to keep blood glucose levels in the normal range, leading to pre-diabetes or type 2 diabetes. Also, higher insulin levels have positive effect on renal tubes in the kidneys, which result in sodium retention and hence high blood pressure.   


Metabolic syndrome 

Metabolic syndrome is a name for a group of risk factors that occur together and increase your risk for heart disease, stroke, and type 2 diabetes. Researchers are not sure whether the syndrome is due to one single cause, but all of the risks for the syndrome are related to obesity. The two most important risk factors for metabolic syndrome are:  

  • Extra weight around the middle and upper parts of the body (central obesity). The body may be described as "apple-shaped."
  • Insulin resistance: The body uses insulin less effectively than normal. Insulin is needed to help control the amount of sugar in the body. As a result, blood sugar and fat levels rise.

Osteoarthritis

It is a disease of joints in which you suffer from pain and stiffness and gradually physical activity is diminished. When your body weight increases, it puts extra pressure on your joints and cartilages exposing them to further damage.    


Sleep apnea 

Sleep apnea is a sleeping disorder in which there is an obstruction in the upper airway and you suffer from brief pauses in your breathing during sleep. The brief pauses lasts from few seconds to minutes. During this period your airways are collapsed resulting in air passing through the shallow passage, which results in loud snoring. According to several clinical studies, overweight and obesity is one of the leading causes of sleep apnea. Although, exact link between obesity and sleep apnea is still unclear, it is believed to be mainly because of the deposition of fat around the neck, which shrinks the airway, making it difficult for you to breathe.   


Stroke 

When you are overweight or obese, fatty materials are deposited or blood clots are formed in blood vessels in the brain or neck. Ultimately blood supply to the brain is cut off resulting in weakness or numbness on one side of the body, difficulty in balancing, loss of speech, double vision, or severe headache, and finally stroke.


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