Here are answers to three common diet and nutrition questions related to alcohol, late-night noshing, and fruits and veggies.I've heard that alcohol, especially wine, can be healthy, and I typically have a few drinks during the week as well as two to three each weekend night.If you're trying to control your weight, watching your alcohol consumption can be essential. Simply having one beer a night adds more than 1,000 calories per week -- an extra 15 pounds per year. A couple glasses of wine over the course of a meal can add as many as 400 calories.The alcohol is what contains most of the calories, so the lower the alcohol content, the lower the number of calories. There are seven calories per gram of alcohol, compared with four calories per gram of either carbohydrates or protein. (Fat contains nine calories per gram.)Alcohol also impairs a dieter's good judgment, which means you may eat and drink more than you normally would. To top it off, most people enjoy eating high-calorie, high-sodium snacks when they drink alcohol -- that's triple the trouble if you're trying to lose weight.From a physiological standpoint, alcohol can cause your blood sugar level to drop more rapidly, which can stimulate your appetite and disrupt your ability to tell when you've had enough to eat.Additionally, this effect can cause fatigue, draining your energy level. Alcohol may also interfere with the absorption of certain vitamins and minerals.Here are a few tips: Stick to beer or wine. Light beer has 100 calories a bottle, compared with 150 for a regular beer. And while 5 ounces of dry wine or champagne will cost you only 100 calories, watch out for sweet dessert wines, which have 226 calories (for 5 ounces).Nix high-calorie mixers. Alcohol itself is packed with calories, but when you add mixers -- soda, juice, syrup -- watch out! Turning rum into a rum-and-cola almost doubles the calories. So either order spirits on the rocks or ask for seltzer as your mixer. Also note that diet soda seems to increase the effects of alcohol -- so be cautious.Skip anything creamy, frozen or fruity. Kahlua and cream or a frozen margarita can have as many calories as an entire meal, plus added fat. A 16-ounce piña colada has almost 1,000 calories.Is it true that you shouldn't eat after 8 p.m.? The latest research coming from scientists at Northwestern University found that calories consumed after 8 p.m. "may increase the risk of obesity, independent of sleep timing and duration."The researchers found that late sleepers who consumed more calories at dinner and after 8 p.m. "had higher fast food, full-calorie soda, and lower fruit and vegetable consumption. Higher BMI was associated with shorter sleep duration, later sleep timing, caloric consumption after 8 p.m. and fast-food meals."When they're tired or stressed, many people find it easier to reach for ice cream, chips and other comfort foods while relaxing in front of the tube. Eating during prime-time TV hours is common -- and often done mindlessly. So what should you do?Be prepared. Eating at night in moderation can be OK. The problem arises when we overdo it and eat a pint of ice cream instead of the half-cup serving the package recommends. To overcome this habit and cut down on your calorie consumption, find a few nighttime calorie bargains, lower-calorie substitutions for what you typically eat. Also, make sure to get those high-calorie snacks out of the house.If you don't want to find substitutes for your favorite snacks, try measuring one serving of your favorite food and eating only that much. Put away any leftovers before you start to eat. Never eat directly out of a bag or box -- that's just asking for trouble!Snack consciously: Pay attention to your snacks, especially if you're in front of the TV or your computer or at the movies.I'm trying to lose weight. Is it true that I should avoid eating lots of fruits and vegetables because they're high in carbohydrates? To give you some background: Sugars, starches and fiber are all members of the nutrient category called carbohydrates and are your body's main source of fuel. All carbohydrates (fruit, vegetables, breads and dairy products) contain some natural sugar. For example, fruits and vegetables contain fructose and glucose, milk contains lactose, and grains contain chains of glucose linked together.Because the sugar in fruits and vegetables occurs naturally and is combined with many beneficial vitamins, minerals and other disease-fighting compounds, the pros of including these foods in your diet definitely outweigh the cons. These foods are nutrient-dense, which means they're low in calories but high in the good stuff. They're also rich in fiber and water, so they help you stay full longer. Since weight loss requires that you take in fewer calories than you expend, fruits and vegetables are ideal for helping you stay satisfied while sticking to a weight-loss plan.Also, you might want to separate fruits and vegetables. Fruits typically are higher in sugar than vegetables, and vegetables are generally lower in calories on a per-gram basis.Don't get me wrong, fruits are still an important part of your diet, but you should not consider fruit a free food. Most nonstarchy vegetables are very low in calories and sugar, and you can eat as much as you like.Charles Platkin, Ph.D., is a nutrition and public health advocate and founder of DietDetective.com.