Signs and Symptoms
Obesity is usually determined by body mass index (BMI), which is a formula that calculates the ratio of your height to your weight.
- BMI 25 to 29.9 (overweight)
- BMI 30 and above (obese)
- BMI 40 and above (extremely obese)
A high waist-to-hip ratio (indicating that fat is centered around the waist) increases the risk for developing serious, even life-threatening conditions associated with obesity. Generally, for men a ratio of .90 or less is considered safe. For women, .80 or less is considered safe.
Conditions that may accompany obesity include:
- High cholesterol (including high triglyceride levels)
- High blood pressure
- Heart disease
- Sleep apnea (episodes when a person stops breathing while asleep)
- Cognitive dysfunction
What Causes It?
Researchers know that obesity is the result of eating more calories than we burn off through activity, but a number of factors contribute to obesity:
- Diet. Eating high-fat, high-calorie foods causes weight gain.
- Lack of exercise. Sedentary people do not burn as many calories as active people.
- Genetics. Your genes may influence how much fat your body stores and where it is stored. But genes alone do not mean you will be obese.
- Age. People gain weight as they get older, because they lose muscle mass as they age.
- Psychological issues. Some people overeat when they are upset or stressed.
- Medications. Some drugs, such as corticosteroids, blood pressure medication, and tricyclic antidepressants, can cause you to gain weight.
- Medical problems. Rarely, obesity is due to a medical problem such as Cushing syndrome (where the adrenal glands produce too much hormone) or hypothyroidism (where the thyroid gland does not produce enough hormone). Conditions such as osteoarthritis cause people to be less active, which can lead to weight gain.
- Prenatal environmental factors. Several studies show that adult men and women who were born small for their gestational age are more likely to be overweight or obese than those who were of normal size at birth. Maternal smoking and excess weight gain is also associated with offspring obesity.
The following factors may increase your risk for becoming obese:
- Living in an industrialized country, especially the United States
- Having family members who are overweight or obese
- Not being physically active
- Eating a high-fat diet
- Taking certain prescription medications
- Having a hormone disorder, such as Cushing syndrome or hypothyroidism (underactive thyroid)
- Being emotionally stressed (from the death of a loved one, for example), which may cause overeating
- Prenatal exposures, such as smoking
- Low-income individuals, the most inexpensive foods tend to be high in fat and sugar
- Early sexual or physical abuse
The best way to prevent weight gain is to eat a healthy diet and exercise daily. Keeping a food and exercise journal, where you record what you eat and how long you exercise, is an excellent way to get started.
Organizations such as the American Diabetes Association, the American Heart Association, and the American Dietetic Association have developed guidelines that promote weight loss and healthy eating. These guidelines recommend that no more than 30% of your total calorie intake should come from fats. Overall, you should eat a wide variety of foods, especially fruits and vegetables, to stay healthy and maintain proper weight.
Many studies show that exercise, from moderate to intense, helps prevent obesity. The Centers for Disease Control and Prevention and the American Academy of Sports Medicine recommend at least 30 minutes of moderate aerobic activity (such as a brisk walk) at least 5 days a week. You do not have to exercise for 30 minutes at a time; 10 minutes, 3 times a day, is also effective. In fact, any exercise, from taking the stairs to cleaning the house or working in the garden, is beneficial. You should also include muscle-strengthening activities, lifting weights or working with resistance bands, 2 days a week.
What to Expect at Your Doctor's Office
Your doctor will use BMI to diagnose obesity. To determine BMI, weight in kilograms is divided by height in meters, squared. You can find online BMI calculators that do the math for you. The following BMI ranges are most often used to indicate that a person is overweight or obese:
- BMI 25 to 29.9 (overweight)
- BMI 30 and above (obese)
- BMI 40 and above (extremely obese)
Your doctor may also measure your blood pressure and percentage of body fat and order blood tests to check cholesterol levels and determine how well your thyroid is functioning.
Losing weight, and then maintaining a healthy weight, involves a combination of diet, exercise, and other lifestyle modifications. Although some medications, herbs, and supplements may help you lose a little weight, you still must eat fewer calories and exercise more to see any real effect. And you must make those behavioral changes stick to keep weight off. For severe obesity, bariatric surgery (which physically restricts the amount of food a person can eat) may be an option.
To lose weight, you must eat fewer calories and increase your physical activity to burn more calories. The key to losing and keeping off weight is to set realistic goals and incorporate effective lifestyle changes into your daily routine.
Exercise can help you lose weight, especially in the first 6 months, and maintain your desired weight in the long term. Exercise not only contributes to weight loss, it also decreases abdominal fat and improves heart health, lowers blood pressure, and helps keep blood sugar levels in check.
If you are not used to exercising, start slowly and build up to 30 minutes a day for at least 5 days a week. An ideal exercise program includes aerobic activity (such as walking, swimming, or biking), strength training (lifting weights), and flexibility (stretching). If you are severely obese or have other medical problems, talk to your doctor before starting a new exercise program.
You may be sore at first. Some muscle soreness is normal. However, if you have pain that lasts more than 2 hours after your workout, see your doctor before continuing.
Some medications help promote weight loss, but there are no drugs to cure obesity. Weight loss medications should be used in addition to diet, exercise, and other lifestyle modifications. Many of these drugs are available by prescription only and some have serious side effects.
Over the Counter Medications
Orlistat (Alli): Alli reduces the amount of fat your body can absorb from foods. Side effects include oily stools, flatulence, and diarrhea. Alli also blocks your body from absorbing some vitamins and nutrients, so you should take a multivitamin daily. Weight loss with Alli tends to be modest, and you still need to follow healthy diet recommendations (eating more fruits, vegetables, and whole grains, and less saturated fat). Common side effects are bloating, flatulence, and fatty or oily stools.
- Sibutramine (Meridia) boosts metabolism, enhances energy level, and promotes a feeling of fullness. Meridia is moderately effective. Studies show that people who take Meridia lose about 10 pounds more than those who just followed a low-calorie diet. Side effects include dry mouth and insomnia. Meridia cannot be taken by people with a history of stroke, seizures, or heart, liver, or kidney diseases.
- Orlistat (Xenical) reduces the absorption of fat from foods. Side effects include oily stools, flatulence, and diarrhea. It is approved for over-the-counter sale in the U.S. as Alli.
- Phentermine suppresses appetite. Serious potential side effects include pulmonary hypertension and heart valve defects. Phentermine is similar to an amphetamine and should not be taken by people with high blood pressure, heart disease, glaucoma, or those taking antidepressant medications.
Bariatric or weight loss surgery may be considered in cases where people are severely obese and lifestyle changes have not worked. It uses bands or staples to create a small pouch at the top of the stomach. The pouch reduces the amount of food that can be taken into the stomach. Physicians carefully select individuals for surgery, and patients must undergo psychological testing and counseling. People who have had bariatric surgery must be monitored by their doctor afterward to make sure they get enough essential nutrients. Procedures include:
- Roux-en-Y procedure (gastric bypass). Permanently reduces the size of the stomach; vomiting is the most common side effect.
- Gastric banding. An adjustable silicone band is placed around the stomach, decreasing the amount of food that can be eaten. The band can be adjusted or removed.
- Laparoscopic vertical sleeve gastrectomy. The stomach is restricted by stapling and dividing it vertically and removing more than 85% of it. The stomach that remains is shaped like a very thin banana.
Complementary and Alternative Therapies
Diet plans are enormously popular. They range from traditional low-fat, high-carbohydrate diets to high-protein, high-fat, low-carbohydrate diets. The truth is, no specific diet works for everyone, and no diet works without the other essential components of weight loss, exercise and stress management.
The U.S. Department of Health and Human Services says a healthy diet:
- Emphasizes fruits, vegetables, whole grains, and fat-free or low-fat dairy products
- Includes lean meats, poultry, fish, beans, eggs, and nuts
- Is low in saturated fats, trans fats, cholesterol, salt, and added sugar
Beware of diets that promise quick, substantial weight loss; they often do not contain enough of the nutrients your body needs to stay healthy, and you are more likely to go off the diet and binge eat and gain the weight back. Weight loss of about 1 to 2 pounds per week is considered safe and sustainable. Before trying any diet, it is important to consult a health care practitioner to determine which plan is right for you.
Nutrition and Supplements
Most evidence for using these supplements in weight loss is either scant or mixed. None of these supplements will work for significant weight loss without changes to diet and exercise habits. Talk to your health care provider before using these supplements.
5-Hydroxytryptophan (5-HTP) (600 to 900 mg per day): 5-HTP is thought to reduce hunger cravings by boosting serotonin levels in the central nervous system, which may reduce appetite and lessen food cravings. However, 5-HTP has been associated with eosinophilia myalgia syndrome (EMS), a rare and potentially fatal blood disorder, although it is not clear whether 5-HTP actually contributes to developing the disorder. In addition, people who take antidepressant medications or herbs and supplements with antidepressant effects (such as St. John's wort and SAMe) should avoid 5-HTP. Talk to your doctor before taking 5-HTP.
Fiber: Fiber may help lower insulin levels (insulin controls the amount of sugar in the blood) and help you feel fuller.
Calcium: Calcium may play an important role in fat burning. Population studies show that higher dietary calcium levels are associated with lower BMIs.
Zinc (15 to 20 mg per day): may increase lean body mass and reduce or stabilize the amount of fat. The reason may be that zinc increases levels of leptin, a hormone in the body that helps you feel full. Zinc can interact with certain medications, including Cisplatin, and some antibiotics. Check with your physician.
Vitamin D and calcium (1,000 mg of calcium and 400 IU of vitamin D per day): One study found that in postmenopausal women, those who took calcium and vitamin D supplements were less likely to gain small to moderate amounts of weight than those who took placebo. Calcium can interfere with certain medications, including some antibiotics and thyroid medications. Calcium must be in balance with other minerals and electrolytes in the body, such as magnesium and phosphate. If you have medical issues that alter these levels, speak with your physician before taking calcium supplements.
Chitosan: Chitosan is a fiber-like supplement made from the shells of crustaceans, such as shrimp and crab. While some studies show that chitosan (in addition to a low-calorie diet) reduces weight, it is unclear whether the supplement itself, the low-calorie diet, or a combination of both led to the weight loss. Other studies show mixed results. Chitosan may have a blood-thinning effect, and therefore can interact with blood-thinning medications, such as warfarin (Coumadin) and aspirin.
Pyruvate: Pyruvate is a substance that occurs naturally in the body, where it is converted to lactic acid. There is some evidence that it may help reduce body fat, possibly by increasing the body's metabolic rate. Other studies show no effect. If you have gastrointestinal symptoms, use special caution. DO NOT use pyruvate if you have cardiomyopathy unless supervised by your cardiologist.
Hydroxycitric acid (HCA): This substance, extracted from the fruit Garcinia cambogia, is similar to citric acid (found in oranges and citrus fruits). In test tubes, HCA stops carbohydrates from being stored as fat, and some animal tests indicate HCA can suppress appetite. However, studies in humans show mixed results.
Chromium: Chromium or chromium picolonate is a popular supplement among body builders and those trying to lose weight and build more lean muscle mass. However, results from scientific studies have been mixed, and its effects are small compared to those of exercise and a well-balanced diet. In a review of 10 studies, researchers found a significant reduction in body weight among chromium-treated patients compared to placebo-treated patients. Chromium may improve blood sugar (also a risk factor for heart disease), particularly in those with diabetes and glucose intolerance, but should not be taken for that purpose without a doctor's supervision. People with kidney or liver disease or psychiatric illness should check with their doctor before taking chromium supplements. Chromium may interact with synthroid and/or insulin. Large doses of chromium can cause kidney damage.
Glucomannan (1 g, 3 times per day, 1 hour before each meal): Glucomannan is a kind of insoluble fiber that appears to reduce blood sugar levels and may help promote weight loss. People with diabetes should not take glucomannan without their doctor's supervision. Glucomannan may interfere with the absorption of several medications.
Psyllium (Plantaginis ovatae): Psyllium, a kind of soluble fiber, may reduce hunger cravings by making you feel full. Adding psyllium and other sources of fiber into your diet may aid weight loss. If you have gastrointestinal issues speak with your physician before adding psyllium to your regimen. Fiber supplements may interfere with the absorption of many medications, so people need to take them hours apart from one another. Speak with your physician.
Green tea (Camellia sinensis): Researchers think that polyphenols (chemical substances found in plants that have antioxidant properties, protecting cells in the body against damage) found in green tea extract may boost metabolism and help burn fat. However, studies have shown mixed results so far. In addition, the extracts used in the studies contained caffeine, which can increase metabolism and promote weight loss. If you are sensitive to caffeine, or have anxiety or heart problems, you may want to limit how much green tea you consume.
Guggul (Commiphora mukal, 25 mg of guggulsterones, 3 times per day): A common ingredient in several Ayurvedic medicines used to treat obesity. Studies suggest that overweight people who take these Ayurvedic remedies lose slightly more weight compared to those who do not take them. Guggul can cause mild diarrhea and nausea, and may interact with the following medications: blood-thinning drugs (anticoagulants), birth control pills, thyroid hormone, tamoxifen, and estrogens. People who take these medications should not take guggul. In addition, people who have or have had hormone-sensitive cancers (breast, ovarian, or prostate cancer) should not take guggul.
Cayenne or capsaicin (Capsicum frutescens, 6 to 10 g per meal): Preliminary evidence indicates that capsaicin (the substance that makes chili peppers taste hot) may reduce hunger and help the body burn fat, particularly when eating a high-fat diet. More research is needed to confirm these early findings, however. Cayenne may increase blood thinning and may interact with blood-thinning medications, such as warfarin (Coumadin) and aspirin. If you have gastrointestinal issues, speak with your physician before taking capsaicin.
Hoodia (Hoodia gordonii): A number of media reports on hoodia have suggested it could be an effective weight loss supplement. However, the research on hoodia is preliminary, so no one knows whether hoodia works or whether it is safe. In addition, news reports now suggest that most hoodia supplements on the market today contain little if any of the actual herb. Until more research is done, and trusted sources exist to provide the herb, it is best to avoid hoodia.
Few studies have examined the effectiveness of specific homeopathic remedies, and there is no single or combination homeopathic remedy that will help all people lose weight. However, individualized homeopathic therapy can be designed to aid weight loss by addressing metabolism, digestion, and elimination. Before prescribing a remedy, homeopaths take into account a person's constitutional type, includes your physical, emotional, and intellectual makeup. An experienced homeopath assesses all of these factors when determining the most appropriate remedy for an individual.
Many studies have found both acupuncture and acupressure can improve weight loss slightly. Acupuncture is believed to promote weight loss by stimulating points on the body that boost serotonin levels. (Higher serotonin levels are thought to suppress appetite.) One well-designed study found that people who received electrical acupuncture of the ear (auricular acupuncture) reduced their appetite.
Cognitive Behavioral Therapy
Besides changing diet and exercise habits, successful weight loss often requires other behavioral changes to keep the weight off. That might include setting reasonable weekly or monthly goals, such as how much exercise or how much weight loss you want, and finding ways to reward yourself that do not involve food. Working with both a dietician and a behavioral specialist can help you put these practices into play.
It also helps to reduce the stress that leads to overeating by practicing relaxation exercises, such as yoga, meditation, or tai chi.
Finally, it is hard to lose weight without support. Support groups, such as Overeaters Anonymous or Weight Watchers, can help you stay focused on your goals. They also allow members to share successes and encourage each other.
Although studies are mixed, some evidence indicates that hypnosis (especially when used in combination with cognitive behavioral therapy, exercise, and a low-fat diet) may help overweight or obese people lose weight.
Pregnant women should not take any herbal remedies or over-the-counter or prescription medications for weight loss.
Obese women who become pregnant are at an increased risk for the following:
- Gestational diabetes. A diabetic condition that appears during pregnancy and usually goes away after the birth of the baby
- High blood pressure
- Preeclampsia. A potentially fatal condition causing high blood pressure, fluid retention, and protein in the urine; may cause abdominal pain and vomiting
- Caesarean sections
- Fetal distress. A condition in which the baby does not receive enough oxygen
Prognosis and Complications
People who are overweight or obese increase their risk for developing the following conditions:
- Type 2 diabetes
- High blood pressure
- Coronary artery disease
- High cholesterol
- High levels of triglycerides (fat) in the blood
- Heart failure
- Respiratory problems (such as sleep apnea)
- Circulatory problems (such as varicose veins)
- Gallbladder disease
- Breast cancer (after menopause) and endometrial cancer
- Prostate cancer
- Colorectal cancer
- Depression, bipolar disease, and agoraphobia
Eating and exercise habits are hard to change. Many people are able to lose at least 20 pounds with diet and exercise plans, but only about 10 to 20% can maintain that weight loss for a long period of time. Losing just 15 to 20 pounds, however, can reduce the risk of serious complications, such as diabetes and heart failure, by 10 to 25%.
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