1. Is it true that food eaten late at night (e.g., after 8:00 p.m.) is more likely to turn into body fat? The idea that eating late at night leads to greatet weight gain is not necessarily true. Weight gain is dependent on caloric intake and caloric expenditure. If people eat more than they expend, they will gain weight regardless of whether the calories come from breakfast, dinner or a late-night snack. However, in reality, people who eat alot of food late at night tend to consume more calorie-dense foods and thus eat more calories, which can cause weight gain. The bottom line: It is not when a person eats but what and how much. If a person finds him or herself  mindlessly eating chips at 10:00 at night while watching TV, then it might be helpful to reverse this fat-promoting behavior by making a behavioral plan that includes not eating after 8:00 p.m.
  2. Does exercise curb appetite? Research suggests that appetite decreases for about the first hour after strenuous exercise and then normalizes. However, appetite regulation is a very complex process relying on insulin, hormones, psychological factors and blood sugar levels, this complexity makes it difficult to generalize the effects of exercise on appetite. Overall, people who participate in moderate exercise tend to eat about the same number of calories or only slightly more than they would if they didn’t exercise. Competitive athletes overall do consume a lot more food than usual after exercise,  but they usually burn off much more than the excess calories they consumed.
  3. How long should a person wait to exercise after eating? Its is generally recommend that exercisers wait about three hours after eating a full meal to engage in strenuous exercise program. That is about how long it takes for a balanced meal including some carbohydrate, protein and fat to move from the stomach into the small intestines, where nutrients are absorbed and energy becomes available. Exercising before food has had time to empty from the stomach can cause cramps and abdominal discomfort. But people respond differently and there is no set amount of time to wait. If an individual exercises in the morning, a quick carbohydrate-dense snack might help to provide some energy during the workout without a lot of discomfort.  Generally, carbohydrates are yhe digested in about an hour , while protein takes about two hours and fat about four hours. But remember, most food are a combination of the three types of macronutrients.
  4. Which is better for weight control, consuming three square meals or eating five or six small meals spread out over the day? Weight control is a balance of ”calories in” versus “calories out.” So ultimately, it does not matter if the calories come in the form of the three larger meals or five to six smaller meals: however, some people find that they are better able to control  their caloric intake in one way or the other. For instance, people who consume three or fewer meals per day may find that when they eat they feel famished and overeat to compensate. Earing fewer meals spaced throughout the day may help with calories control. On the other hand, someone who eats five to six meals per day may forger to make them small meals and instead end up consuming more calories than he or she would with three meals. In the end, it is a matter of preference. One strategy for effective meal planning is to determine the total number of calories (or, alternatively, total number of servings from each of the food groups) and divided them somewhat equally throughout the day-whether there are three meals or six. Importantly, people who have diabetes should consume five to six equal-sized small meals to maintain healthy blood sugar levels throughout the day.
  5. Why do some people have a more difficult time losing weight than others?Genetics clearly is a factor in how easily someone lose weight. Also, gender differences play a role, in that when men lose weight they tend to lose abdominal fat first,  whereas women have a more difficult time losing abdominal fat. However, there are additional,  more controllable factors as well, first,  the amount of muscle mass an individual has is directly proportional to metabolism, and thus caloric expenditure. People who have a large muscle mass can more easily lose weight when they control caloric intake than someone who has a low muscle mass. Secondly, people who have more  weight to lose experience a lot of weight-lose success when they decrease their caloric intake and increase physical activity,  because their baseline is often a very high-calorie diet. For example if someone who weighs  250 pounds (114 kg) normally eats 3,000 calories per day and he or she cuts back to 2,000 calories per day and expends 200 more calories per day with more exercise, he or she can easily lose more than 3 pounds  (1.4 kg) in one week. On the other hand, if someone who weighs 125 pounds (57 kg) and normally eats 2,200 calories per day cuts back to 2,000 calories per day and expends 200 more calories per day with exercise he or she will only lose about 0.75 pounds (0.34 kg) in a week. Finally, behavioral factors cannot be ignored.  Some people are more successful at weight loss because they are better able to adhere to a lower-calorie deit and regularly engage in a physical activity.
  6. Are carbohydrates bad? What proportion of carbohydrates, fats, and protein should people eat for optimal weight loss and health? As far as weight loss goes, the proportion of a macronutrients consumed is not what is important. Rather, it is total caloric intake versus caloric expenditure, or “calories in” versus “calories out”. However, foods rich in fiber and protein tend to be the most filling, which in theory would lead to decreased intake of food and calories compared to high-fat foods and low-fiber carbohydrates. It is important to remember that people often eat for reasons other than hunger, and as a result occasionally continue to eat even when they are full. An effective weight-loss program address both the recommended food intake as well as the behavioural factors that sometimes get in the way of success weight loss. Form a heart health perspective, the healthier overall meal plan appears to be a Mediterranean-type eating plan, which is rich in fruits, vegetables, whole grain and omega-3 fatty acids from fish and low in saturated fat, trans fat, sodium and added sugar.
  7. Should people cut out food groups to lose weight? The most successful approach to weight lose and weigt-loss maintenance is to make permanent lifestyle changes that include a healthful eating plan and ample physical activity.  A diet which implies short-term and hard to adhere to changes is not the answer.  Thus, while certain foods are prohibited in various “diets,” a healthy lifestyle allows for all foods in moderation. This means that less healthy food can fit,  as long as they make up only a small portion of the total daily caloric intake. It is essential that an eating plan contain adequate amounts of a variety of foods from each of the food groups to assure balanced nutrients intake.
  8. Should people take a supplement to get adequate nutrition? The science on multivitamins is a inconclusive. In 2006, a National Institutes of Health  (NIH) panel convened to evaluate all of the research on multivitamins and develop recommendations for the public.  The panel’s summary statement was the insufficient high-quality research has been done to be able to asses whether vitamins help in chronic disease prevention.  Two exceptions are the strong indications for folic acid supplement for all women of child-bearing age to prevent neural tube defects in the developing baby and fish oil/omega-3 fatty acid supplement in the prevention of heart disease in people who are at risk.  In general,  most dietitians recommend that people take a multivitamis as a “insurance ” and more importantly, aim to get optimal  nutrition including vitamins and minerals from whole foods such as fruits, vegetables, fish and low or non-fat dairy products.
  9. Are low-fat foods also low in calories? Foods naturally low in fat (e.g., fruits, vegetables, grains) tend to be low in calories. However, foods that are manufactured to be low in fat (e.g., reduced-fat snacks and desserts) can be relatively high in calories. During the process of removing fat, some of the taste and texture of the food items are lost. In an effort to add taste and texture, food manufacturers often add carbohydrates and protein, thus adding calories. like most foods, low-fat foods should be consumed in moderation to avoid weight gain.
  10. Does caffeine improve athletic performance? Research findings are clear: Caffeine enhances athletic performance. Caffeine sustains duration, maximizes effort at 85% of VO2 max in cyclists, and quickness speed in a endurance event. Perceived exertion decreases and high-intensity efforts seem less taxing. Contrary to population opinion, research suggests thag caffeine use combined with exercise does not cause negative effects like water-electrolyte imbalance, hyperthermia, or reduced exercise-heat tolerance. But there is a catch: performance enhancing benefits of caffeine are stronger in non-users (<50 mg/dsy) than regular users (>300 mg/day). In addition to tolerance,  chronic caffeine use contributes to high blood pressure, high blood sugar, decreased bone density in women, jittery nerves, sleeplessness and for many, the dreaded withdrawal symptoms after a brief respite from the stimulant, including headache, irritability, increased fatigue, drowsiness, decreased alertness, difficulty concentrating and decreased energy and activity levels.