2015-03-20

By Dr. Mercola

Do you exercise so you can "eat whatever you want?" Unfortunately, it's not that simple. Even on a basic calorie level, the amount of calories you'll take in by eating a fast-food burger, fries, and soda is probably far more than you'll burn during even a high-intensity workout.

But this is a matter of far more than calories in versus calories out. You do not get fat because you eat too many calories and don't exercise enough. You get fat because you eat the wrong kind of calories.

As long as you keep eating fructose and grains, you're programming your body to create and store fat, regardless of how much exercise you get.

About 80 percent of your ability to reduce excess body fat is determined by what you eat, with the other 20 percent related to exercise and other healthy lifestyle habits such as sleep and stress reduction.

What this means is that if your diet is based on processed junk food, your chances of getting fit and healthy, even if you work out religiously, are quite slim...

A Junk-Food Diet Is Counterproductive to Your Exercise Goals

Eating a poor diet isn't only a matter of "empty calories" causing you to gain weight without getting proper nutrition. Excess sugar and fructose consumption, which is common if you eat a lot of processed foods, is linked to insulin resistance, high triglycerides, heart disease, diabetes, obesity, and cancer.

This is also a driving factor in insulin resistance. According to Dr. Robert Lustig, professor of pediatric endocrinology at the University of California, San Francisco (USCF), whatever organ becomes insulin resistant ends up manifesting its own chronic metabolic disease.

For example, when you have insulin resistance, you can end up with type 2 diabetes, Alzheimer's disease, cancer, heart disease or chronic renal disease.

In addition, refined fructose, typically in some form of corn syrup, is now found in virtually every processed food you can think of, and fructose actually "programs" your body to consume more calories and store fat.

Fructose is primarily metabolized by your liver, because your liver is the only organ that has the transporter for it. Since nearly all fructose gets shuttled to your liver, it ends up taxing and damaging your liver in the same way alcohol and other toxins do.

A Poor Diet Turns on Your Body's Fat Switch

Further, dietary sugar, and fructose in particular, is a significant "tripper of your fat switch." Dr. Richard Johnson discovered the method that animals use to gain fat prior to times of food scarcity, which turned out to be a powerful adaptive benefit.

His research showed that fructose activates a key enzyme, fructokinase, which in turn activates another enzyme that causes cells to accumulate fat. When this enzyme is blocked, fat cannot be stored in the cell.

Interestingly, this is the exact same "switch" animals use to fatten up in the fall and to burn fat during the winter. Fructose is the dietary ingredient that turns on this "switch," causing cells to accumulate fat, both in animals and in humans.

Not to mention, avoiding sugar is especially important if you do high-intensity exercises, which will boost your body's production of human growth hormone (HGH). Consuming carbs within a couple of hours prior to or after such exercise will effectively prevent HGH from being produced.

Junk-Food Diet Promotes Inflammation, Alters Gut Bacteria

Trans fats, fried foods, processed foods, sugar, and grains are highly inflammatory, and this is another risk factor that exercise can't ameliorate. Health problems such as obesity, insulin resistance, type 2 diabetes, periodontal disease, stroke, and heart disease are all rooted in inflammation.

The majority of inflammatory diseases start in your gut. Chronic inflammation in your gut can disrupt the normal functioning of many bodily systems.

Further, if you eat many processed foods your gut bacteria are going to be compromised because processed foods in general will seriously impair healthy microflora and feed pathogenic bacteria and yeast. This, in turn, can further promote chronic disease and weight gain, even if you're a regular exerciser.

Lean people tend to have higher amounts of various healthy bacteria compared to obese people. For example, one 2011 study found that daily intake of a specific form of lactic acid bacteria could help prevent obesity and reduce low-level inflammation.1

Other research found that obese individuals had about 20 percent more of a family of bacteria known as firmicutes and almost 90 percent less of a bacteria called bacteroidetes than lean people.2

Firmicutes help your body to extract calories from complex sugars and deposit those calories in fat. When these microbes were transplanted into normal-weight mice, those mice started to gain twice as much fat. This is one explanation for how the microflora in your gut may affect your weight.

Eat to Exercise, Not the Other Way Around

What you eat can either add to or take away from your exercise benefits, and if you're devoting the time to workout, you want to know how to harness your meals to support your efforts, not detract from them. As noted by sports nutritionist Susan M. Kleiner, R.D., Ph.D.:3

"When it comes to sculpting your body and enhancing your performance, without a diet to support your training you are wasting your time in the gym."

It helps to think of your food as fuel, and consider whether what you're putting in your mouth will best keep your body in optimal working order. Remember, you cannot exercise your way out of a bad diet, but you can eat your way to a fitter and healthier body.

If you're like most people, you're probably eating too many carbs. Your body's need for sugar is, biologically, very small. And when you consume more than you need, your body turns it into fat. If you are a competitive athlete and are not insulin resistant, you can tolerate more carbs.

You do not typically get fat from eating healthy fats—you get fat from eating too many carbs (sugar) or excessive calories. Hence, what you'll find on my list of "fitness foods" below are primarily healthy fats, which is what you'll want to replace the lost carbs with for energy, along with high-quality proteins and a couple of specific nutrients that are particularly beneficial for boosting athletic performance.

The Most Valuable Fitness Foods

The following six foods are those that I believe are among the most helpful in terms of supporting your fitness and overall good health. Aim to incorporate as many of these foods into your diet on a daily or weekly basis, and you'll be off to a great start. Keep in mind that all of the items on this list should be organic, and if possible grass-fed/pastured or wild. We've covered what you shouldn't be eating if you want to get fit… now let's cover what you should.

1. Avocado

Avocados are rich in monounsaturated fat that is easily burned for energy. A medium avocado contains about 22.5 grams of fat. They're also very low in fructose, which is yet another boon, while being high in potassium, which will help balance your vitally important potassium-to-sodium ratio.

Avocados also enable your body to more efficiently absorb fat-soluble nutrients, such as alpha- and beta-carotene and lutein, in other foods eaten in conjunction.

2. Coconut Oil

Coconut oil is nature's richest source of healthy medium-chain fatty acids (MCFAs), which your body sends directly to your liver to use as energy. This makes coconut oil a powerful source of instant energy to your body, a function usually served in the diet by simple carbohydrates. Numerous studies have shown that MCFAs promote weight loss4 and help improve insulin sensitivity and glucose tolerance. Additionally, research has demonstrated that, due to its beneficial metabolic effect, coconut oil also increases the activity of your thyroid.

A sluggish thyroid is one reason why some people are unable to lose weight, no matter what they do. Half of the fat content in coconut oil is lauric acid—a fat rarely found in nature—that could easily qualify as a "miracle" ingredient because of its unique health promoting properties. Your body converts lauric acid into monolaurin, which has anti-viral, anti-bacterial, and anti-protozoa properties, for example. You can add raw organic coconut oil to green juices, smoothies, and even coffee (in lieu of sugar).

3. Wild Alaskan Salmon

Wild Alaskan salmon is an excellent source of essential animal-based omega-3 fats (EPA and DHA), high-quality protein, as well as astaxanthin and other antioxidants—all of which are important nutrients for fitness. Over the last several years, I've vigilantly warned against eating most fish, as virtually all fish these days contains dangerously high levels of mercury and other toxic contaminants. However, there are still some exceptions, and wild Alaskan salmon is one of them, as long as its purity can be verified. You can also get animal-based omega-3 fats and high-quality protein, without a risk of contamination, by eating sardines and anchovies.

4. Organic Pastured Eggs

Organic pasture-raised eggs are a great source of proteins, which are essential to the building, maintenance and repair of your body tissues such as your skin, internal organs, and muscles. They are also the major components of your immune system and hormones. Pasture-raised eggs also contain healthy saturated fats and cholesterol—both of which your body actually needs for optimal health.

Eggs, as well as the chickens they come from, are both healthy sources of protein but ONLY if raised the way nature intended. True free-range eggs, now increasingly referred to as "pasture-raised," come from hens that roam freely outdoors on a pasture where they can forage for their natural diet, which includes seeds, green plants, insects, and worms. Barring organic certification, which is cost-prohibitive for many small farmers, you could just make sure the farmer raises his chickens according to organic, free-range standards, allowing his flock to forage freely for their natural diet, and aren't fed antibiotics, corn and soy.

5. Organic Pasture-Raised Chicken

Research has shown that aerobic exercise most effectively enhances insulin sensitivity when your post-workout meal has relatively low carbohydrate content. After a cardiovascular workout, wait 30-45 minutes, and then consume a high-quality source of protein (whole food) along with a vegetable-type carbohydrate. An example would be a spinach salad and some chicken.

The reason why you'll want to wait a bit after the session to eat is to ride the fat burning wave of your cardio session. However, waiting more than an hour is typically too long, and can start to slow down your metabolism because your body goes into starvation mode. Organic free-range chicken is an excellent source of protein and essential amino acids for muscle growth and maintenance.

6. Antibiotic-Free, Grass-Fed Whey Protein

Whey protein, which is derived from milk, is considered the gold standard of protein by many and is one of the best types of foods you can consume before and after exercise. This is particularly true after a resistance or strength-training workout, when you need a meal that can be rapidly absorbed. Here, whey protein is an ideal choice, particularly along with a higher glycemic (fast released, starchy) carbohydrate, such as a banana. The potassium in the banana seems to help with recovery. Ideally, you'll want to consume it 15-30 minutes after your intense weight-training session.

If you want, you can take 20 grams of whey protein (make sure there's no added sugar) 30 minutes before exercise, and another serving about 30 minutes afterward. This can help increase both fat burning and muscle building. According to a 2010 study, consuming whey protein (20g protein / serving) 30 minutes before resistance training can boost your body's metabolism for as much as 24 hours after your workout.5 If you are only going to do one whey meal, then your post-workout meal is the most crucial, especially if your aim is to increase your muscle growth.

When You Eat After Exercise Matters

Aside from avoiding refined fructose especially if you are insulin resistant, remember to combine a quality protein with a veggie carb in your meals, no matter whether it's a resistance-training day, an interval-cardio day, or a non-workout day. However, after strength training (as opposed to cardio training), your body tends to need more rapidly absorbed nutrients and a higher glycemic (fast released, starchy) carbohydrate. Another slight difference between interval cardio and strength-training days is the timing of your meal. In this regard, when you eat is nearly as important as what you eat:

After cardio, you want to wait 30-45 minutes and then consume a high-quality protein (whole food) and vegetable-type carbohydrate. (For instance, a spinach salad and some chicken or high-quality whey protein).

After a resistance workout (muscle-building day), the ideal time to consume your post-workout meal is 15-30 minutes after finishing your session, in order to help repair your damaged muscles. Here, whey protein is an ideal choice as it's predigested and therefore rapidly digested and easily assimilated, along with, as mentioned, a higher glycemic (fast released, starchy) carbohydrate, such as a banana.

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