One week we are being told to eat five portions of fruit and vegetables a day and then the week after it's being upped to seven.
Some people believe that eight glasses of water a day is a vital part of our diet, others warn that excessive water intake can be dangerous. How are we supposed to know what to believe?
We caught up with Michelle Colvin, health and fitness expert and sole owner of weight management company MEAE, to get some answers. Here she exposes five nutrition myths and tells us what we should really be doing.
Don't eat after 8 pm
If you're mindlessly popping crisps in your mouth while propped up in front of the television, by all means, late-night junk food binges aren't smart. But for busy active people, skipping dinner after returning from an evening workout will do more harm than good. If you allow more than two hours to pass before eating after exercise you'll store 50 percent less glycogen in your muscles. That means less energy for the next day and your next workout.
If your evening workout or a late night at the office pushes dinner after 8 pm, eat a moderate-sized, balanced meal of carbohydrates and protein such as a skinless grilled chicken breast and a baked potato, or a turkey sandwich with low-fat milk and fruit.
Be sure to eat one or two healthy snacks between lunch and dinner to prevent excessive hunger when you finally do sit down to dinner. This could mean the difference between eating the whole chicken versus just the chicken breast.
Eating at night is not in itself unhealthy, nor does it make you fat. If you're worried about weight gain, pay more attention to how much you eat than what time you eat. Taking in more calories than you burn will add pounds no matter when you eat them.
Don't snack between meals
This may be what you were told as a child, but as an active person, you need more than three meals a day to keep you going. Think about it. If you eat only three times over your average 16-hour day (closer to 18 hours on some days), you may go without eating for as long as five to eight hours. With gaps that big, no wonder you're slumping at 3 pm.
If more than three hours go by between meals, treat yourself to a snack to prevent dips in your energy levels, to keep you mentally sharp and to keep your metabolism burning. Most active people should have about three healthy snacks a day, with the emphasis on healthy.
Look at snacking as a chance to get more good-for-you foods into your day. Good choices include fruits, low-fat yoghurt, nuts, cereal with low-fat milk, whole wheat crackers and cheese, and even a cup of soup or a small sandwich.
Work out on an empty stomach
People skip eating before a workout for a range of reasons - from fear of an upset stomach to a desire to lose weight. You may even have heard that exercise on an empty stomach helps burn fat. Actually, the reverse is true. Recent studies show that you'll burn more fat and preserve lean muscle mass during exercise if you begin your workout with some fuel in your stomach.
If you haven't eaten for a while, (overnight for morning workouts, for instance), your liver glycogen stores become depleted, leading to low blood sugar and earlier fatigue during exercise. Studies show that athletes can train longer and faster when they consume 0.5 grams of carbohydrate per pound of bodyweight 90 minutes before exercise.
If you don't have 90 minutes for a pre-exercise meal, eat a small (25 to 30 grams) carbohydrate-rich snacks such as a banana or sports drink.
The more protein the better
Unfortunately, this misconception, along with the popularity of low-carb diets, has to lead many people to eat more protein than they need. While getting adequate protein is crucial to both increasing muscle mass and ensuring muscle recovery, overdoing it will lead to overall poor energy levels and delayed recovery. And as with any form of excess calories, if you don't burn it, protein will turn to fat.
People who exercise at least two times a week need about 0.5 to 0.75 grams of protein per pound of body weight. Good protein sources include fish, poultry, lean meat, soy products, eggs and low-fat dairy products like milk, cottage cheese and yoghurt.
Frozen and canned fruits and vegetables have no nutritional value
Fresh is usually best, but not if they're sitting around your kitchen counter (or at the supermarket) for days losing nutrients. Studies show that canned and frozen fruits and vegetables can be as nutritious as fresh because they're usually processed at the peak of freshness when nutrient content is highest.
And since active people on a 2,000-a-day-calorie diet should get at least nine servings a day (according to the Food and Drug Administration's 2005 Dietary Guidelines), you need to get your fruits and veggies where you can, and not shun the canned or frozen varieties.
Strive for 2 cups of fruit and 2.5 cups of vegetables a day. When buying frozen or canned fruits and veggies look for low sodium content and avoid those with added sugars. With fresh produce, buy what's in season and don't let them sit for more than two or three days before eating.
After more advice from Michelle? Check out MEAE's website here.
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