No question about it, burning fat is a 24/7 endeavor. To keep the fires hot, you need to eat every 2-3 hours throughout the day. Not only that, but you must choose the right foods in the right amounts to keep your metabolism revved up so your six pack will be ready for its close-up.

The way we see it, there are 12 fundamentals—laws, if you will—that are all you need to shed that unwanted blubber from your midsection and elsewhere. Most of them are nutrition-driven, but training comes into play as well. Your mass-gaining phase is over for the time being; now it’s time to get lean. These 12 laws of fat-burning will help get you there.

1. Slash (Calories) and Burn

Step 1 revolves around simple math: You must eat fewer calories than your body is accustomed to in order to drop bodyfat. When a calorie shortfall is created, the body responds by digging into body-fat reserves to make up the difference. And presto, you grow leaner. All other laws aside, this one heads the list every time, no matter what dietary approach you take.

Do this: Most guys who are fairly active and exercise regularly burn about 18 calories per pound of bodyweight or more per day. On that basis, a 200-pounder would consume 3,600 calories daily. To start dropping body fat, reduce your calories to between 14-16 per pound of bodyweight per day on workout days, or 2,800-3,200 calories daily. On nonworkout days, drop to about 12 calories per pound per day (2,400 calories for the guy who’s 200lbs).

The easiest way to cut calories? Eliminate excess dietary fat—meaning no butter, oils, or salad dressings (low-fat or fat-free dressings are OK); remove the skin from chicken; substitute egg whites for most of your whole eggs; avoid whole-milk dairy products; and ditch marbled red meats such as rib-eye for lean cuts such as flank. Keep some healthy fats in your diet, such as salmon, mixed nuts, peanut butter, and avocados.

2. Curtail Carbohydrates

Though calorie control is a must, hormonal control is nearly as important. Coupled with calories, hormones govern fat-burning. Suppress fat-storing hormones and you can expect a significant amount of body fat to melt away. The ideal way to control these hormones is to keep your carbohydrate intake in check, since carbs kick up insulin, a hormone that inhibits fat breakdown and drives fat storage. Eat fewer carbs and insulin levels tend to moderate, leading to fat loss.

Of course, not all carbohydrates are equal. In short, fast-digesting carbs tend to create a large insulin burst, leading to more potential fat gain. These carbs include white bread, most cold cereals, any sweets, rice cakes, white rice, and white potatoes. Conversely, slow-digesting carbs (found in whole-grain breads, oatmeal, sweet potatoes, and legumes) don’t cause much of an insulin rise, so these should make up the vast majority of your carb consumption.

Do this: The common sense approach is to halve your carbohydrate portions. If you tend to eat a large bagel for breakfast, eat only half and save the rest for tomorrow, or simply eat a smaller bagel. If you typically eat 2 cups of pasta at dinner, eat just one. In time, you’ll see the effects of insulin control.

As for carb choices, the aforementioned bagel should be 100% whole wheat, not white. At all times during the day, in fact, choose whole-grain foods over refined ones, the only exception being immediately after a workout, when fast-digesting carbs reign supreme for boosting insulin and replenishing muscle glycogen stores (see Law 8). Keep carbs to less than 2g per pound of bodyweight per day.

3. Stress Protein

Is a calorie truly a calorie? Not always, because different types of calories can affect your body and your results differently. Dietary fat, for example, is more “fattening” than protein or carbs because it’s less likely to be used to build your body. Granted, carbs can potentially make you fat, but they also directly fuel your training. Protein? That’s a no-brainer: It builds muscle. Fat does neither, but it isn’t useless; moderate amounts of it support vitamin absorption and help manufacture hormones.

But if you’re trying to get ripped, you must minimize your consumption of fat. Protein, on the other hand, not only adds to your muscle—key in boosting the metabolism—but actually increases your metabolism more directly. The body burns more calories processing protein than it burns to process carbs or fat, known as the thermic effect of food. That’s the main reason diets that include a lot of protein result in greater fat loss than low-protein diets, even when both diets contain the same amount of calories.

Do this: We can’t harp on this advice too much: Eat at least 1g of protein per pound of bodyweight every day. Your major protein sources should be lean meats (chicken, steak, turkey breast, tuna), egg whites (the yolks contain the fat, so discard most of them when you’re trying to lose fat), protein powder (whey or casein), and low-fat cottage cheese. As for fat, limit it to 20-30% of your total daily caloric intake.

4. Never Eat Carbs by Themselves

When attempting to lose body fat, insulin control is crucial. The total amount of insulin released by the body isn’t related to just how many carbohydrates you eat but how fast those carbs are digested. Refined carbs digest quickly, raising insulin levels substantially, which is why you should avoid them. But if you do happen to eat, say, a bowl of cold cereal (typically a fast-digesting carb), you can still take measures to ensure those carbs digest more slowly. This will cause less insulin to be released and therefore have less of an impact on your ability to burn fat.

Do this: One way to slow digestion is to eat carbs with protein and small amounts of fat. Never eat carbs alone. Accompany that bowl of cereal, for example, with scrambled egg whites or cottage cheese. Alternatively, you could eat plenty of vegetables, such as broccoli, cauliflower, green beans, and green salads, with your meals. These foods actually slow the breakdown and digestion rate of all carbohydrates.

5. Never Eat Carbs Before Bed

Once again, it’s about hormones. At night your insulin sensitivity decreases, meaning your body must release more insulin than usual to put any carbohydrates you eat at night to use in the body. And by now you know that higher insulin levels can decrease fat-burning and enhance fat storage. In addition, the body naturally produces a fat-liberating hormone called growth hormone within the initial 90 minutes of sleep.

GH not only increases fat-burning but is required to build mass and strengthen the immune system. Yet carbs put a damper on GH release, so it’s ideal to go to bed under one of two scenarios: on an empty stomach, or, even better, having consumed only protein, no carbs. This allows blood glucose—the high-tech name for digested carbs circulating in the blood—to remain low, which facilitates the rise in nocturnal GH production.

Do this: Don’t eat anything about three hours before bed. A better option is to eat only protein meals the final four hours before bed, with one protein meal immediately before bedtime that includes only protein, such as a casein shake, low-fat cottage cheese, or chicken breast. You can, however, eat a small serving of vegetables here if you wish.

6. Use Nitric Oxide at Night

Nitric oxide is the compound that opens everything up, and, not surprisingly, it’s one of the best fat-burning products on the market. NO supports “the pump” when taken before training, enhancing blood flow to muscles by allowing more blood to make its way to tissues, including muscles, which can help maximize hypertrophy and boost metabolism. This arginine-based supplement is also effective when taken before bed, when it can exert a profound surge in GH levels and support fat-burning.

Do this: Within 30-60 minutes of bedtime every night, take a 5-10g dose of a nitric oxide supplement that doesn’t contain caffeine on an empty stomach

7. Eat More Meals Per Day

Sure, calories and hormones can determine whether your body deposits food into muscle or as body fat, but meal frequency, or how many times you eat each day, affects your overall metabolism. Every time you eat, the body’s calorie-burning engine, also known as metabolism, slightly increases. This is especially true for meals that contain protein. So if you eat six times a day, you’ll experience six metabolic surges a day, rather than just four if you eat only four times a day. And, of course, eating seven or eight times per day would be even better than six. This is one way to lean out without having to drastically reduce calories. Frequent feedings tend to increase the chance that what you eat will make its way into muscle tissue rather than being packed away as body fat.

Do this: Eat 6-8 small meals per day, spaced 2-3 hours apart. Don’t go longer than three hours without eating—your body will go into starvation mode, which can cause you to store body fat and make it more likely that you’ll overeat at your next meal. Speaking of overeating, just because you’re consuming more meals doesn’t mean you should take in more total calories. Determine your ideal daily caloric intake for fat-burning (see Rule 1) and divide that more or less evenly between your 6-8 meals.

8. Prioritize the Post-training Meal

After you train, it’s difficult to gain body fat. Why? Depleted, broken-down muscles soak up both protein and carbohydrates for growth and recovery. If you eat too little at this time, you may actually set yourself back by impeding recovery; supporting recovery and growth actually increases metabolism while impeding it slows metabolism. In terms of spurring recovery and growth, just about the most counterproductive thing you can do after a hard workout is starve yourself.

Do this: Consume 30-40g of protein powder such as whey powder and casein along with 60-80g of fast-digesting carbs (a large baked potato, 4-5 slices of white bread, or a large sports drink such as Gatorade) as soon as possible within an hour after training.

9. Avoid Fast Carbs Pre-Workout

When you hit the gym, the body releases a fat-liberating messenger called epinephrine, which attaches itself to fat cells and allows fat to be burned as fuel. And, you guessed it, carbohydrates come into play here. Refined carbs consumed before training suppress the exercise- and supplement-induced rise in epinephrine compared to eating the same amount of slower-digesting carbs. Refined carbs also boost insulin levels, further hampering fat-burning during the workout. Bottom line, avoid refined carbs altogether before training.

Do this: Fifteen to 30 minutes (or less) before training, consume 20g of protein powder in a whey shake or other protein powder source and 30-40g of carbohydrates to help you train hard all the way through your workout. Stick with slow-digesting carbs here, such as oat bran, oatmeal, rye or whole-wheat bread, fruit, or sweet potatoes. On nonworkout days, eat that meal as a snack and drop your post-workout feeding.

10. Empty Your Glycogen Stores Once Every Two Weeks

Glycogen is the unused and stored form of carbohydrates in muscles. When glycogen stores begin to peak from eating plenty of carbs, the body upgrades its fat-storing ability. Conversely, as glycogen stores are depleted, fat-burning increases. One way to kick-start the fat-burning process is to go extremely low-carb on two consecutive days every couple of weeks. This ensures that you tap into your glycogen stores for fuel, which signals the body to burn more fat.

Do this: Limit your total carbs on two consecutive days every two weeks or so to less than 100g per day. This will require you to know how many grams of carbohydrates are in the foods you eat and have the discipline to be very strict on your intake. Your diligence will be rewarded with a noticeable difference in body fat. After two days, you can return to a more normal, though not excessive, carb intake.

10. Empty Your Glycogen Stores Once Every Two Weeks

Glycogen is the unused and stored form of carbohydrates in muscles. When glycogen stores begin to peak from eating plenty of carbs, the body upgrades its fat-storing ability. Conversely, as glycogen stores are depleted, fat-burning increases. One way to kick-start the fat-burning process is to go extremely low-carb on two consecutive days every couple of weeks. This ensures that you tap into your glycogen stores for fuel, which signals the body to burn more fat.

Do this: Limit your total carbs on two consecutive days every two weeks or so to less than 100g per day. This will require you to know how many grams of carbohydrates are in the foods you eat and have the discipline to be very strict on your intake. Your diligence will be rewarded with a noticeable difference in body fat. After two days, you can return to a more normal, though not excessive, carb intake.

11. Train Until You’re Beat, Not Dead

It’s the age-old question: How many sets do you need, and how much time should you spend in the gym each day? The answer varies from person to person, but when burning fat is the primary goal, a good rule of thumb is to train until you’re pretty beat up, but not to the point at which you’re flattened and thoroughly exhausted. That type of kamikaze training may satisfy your pysche, but it does a number on your anabolic hormones.

Serious fat loss requires you to retain muscle mass, the body’s primary metabolic driver. If you go overboard in the gym, testosterone and growth hormone go into free fall, and your metabolism follows suit.

Do this: Go ahead, train as intensely as you like—just don’t go longer than 75 minutes in any one workout. Do as many sets and reps as you can during this time, using shorter rest periods (60 seconds max), but when your 60-75 minutes end, finish up and go drink your protein/carb shake.

12. Do Cardio at the Right Time

Cardio exerts two benefits: It burns calories and affects hormone levels in the body. Specifically, cardio helps raise levels of norepinephrine. Yet when you do cardio it makes a big difference in how your body handles the hormonal changes. Cardio on an empty stomach allows norepinephrine to readily target fat cells, which triggers maximal fat-burning. On the flip side, if you eat before doing cardio, and particularly if you eat carbs, the fat-blocking hormone insulin rises, making your body less effective at burning fat.

Do this: To ensure that your body is in optimal fat-burning mode, do 30-60 minutes of cardio first thing in the morning before breakfast 4-6 days per week. Feel free, however, to drink your morning coffee (without cream or sugar) and take 6-10g of mixed amino acids or a small amount of whey protein powder mixed in water beforehand. The caffeine will help you burn more fat, as will the amino acids (whether from a supplement or whey protein), as research from Kanazawa University in Japan has found. The aminos will also help prevent muscle breakdown during cardio.

BY CHRIS ACETO AND JIM STOPPANI, PHD