We hear a lot of advice about nutrition, some of it accurate, a lot of it not so much. Some of the nonsense causes us a good deal of discomfort in the form of guilt. Perhaps we feel "not good enough" because of our failure to live up to imagined standards of healthy eating. Here are 7 healthy food legends that you can stop worrying about.

1. Coffee is bad for you

Coffee drinking, in moderation actually does your body's health far more good than harm. Coffee comes from plants, which have helpful phytochemicals that act as antioxidants. One set of antioxidants appears to increase insulin sensitivity, which might explain a lowered risk of type 2 diabetes in people who sip java. A Harvard study of more than 125,000 coffee drinkers found that women cut their risk of type 2 diabetes by 30 percent. Other studies suggest that coffee cuts the risks of Parkinson's disease, colon cancer, cirrhosis and gallstones. Drinking coffee gives your brain a boost, too. Two to three cups a day is the recommended limit for most people.

What about the concern that coffee is dehydrating? It can be. It depends on the dose. Coffee is only a diuretic at high doses -- above 575 milligrams - about 3 cups daily. If you exceed that amount of coffee, drink more water to offset the diuretic effect.

Contrary to popular belief, coffee does not increase your likelihood of getting hypertension. Coffee does increase your blood pressure, but only for a few minutes.

2. Chocolate Causes Acne

Chocolate has been found not to cause nor aggravate outbreaks of acne. These results are backed up by research that shows acne in no way is affected by chocolate. Nor, for that matter, do greasy foods, pizza, or salty snacks, or dairy cause or aggravate acne.

If you do have an outbreak of zits repeatedly after eating a specific food, stay away from that food for a while. Much research suggests that foods do not cause acne, but it has not been proven as fact. If on eating the same food again after a few days the result is an outbreak, the chances are it is an allergic reaction rather than an outbreak of acne.

Acne forms when the oil glands make too much sebum, a waxy substance that along with dead skin cells can clog pores. Bacteria grow and irritate the blocked pore given the red and swollen look to them. Androgen hormone production is at its highest during the teenage years, which stimulates sebaceous glands to enlarge and make more sebum.

Teenagers are not the only ones with acne. Women who are pregnant or in their 40s can have outbreaks, but by the time a person is 50 it usually has run its course. During the teenage years, boys are more susceptible to stronger breakouts than girls, but when they reach around 40, the women take the lead in numbers of flare-ups.

Chocolate has been blamed for many ailments in addition to acne, including tooth decay, obesity, and lacking of food value. Recent scientific studies have suggested chocolate boosts the serotonin in the brain that produces a calming effect and stability. Chocolate lovers will be pleased to know that nutritionists believe chocolate plays a nutritional role in a balanced diet. The facts are that chocolate carries about one-third of an adult's daily requirement of antioxidants.

3. Eating at night makes you fat.

You had plenty to eat at dinner, but late at night the fridge starts calling your name. It's not about being hungry, more about being tired, bored, or just a habit formed after years of indulging in a mid-night snack immediately before going to bed. It's quiet at night, no one is around to see you eat, and it's a peaceful time to enjoy your favorite foods. Eating before going to bed won't make you any fatter that the snack you had at mid-afternoon. Several authoritative studies suggest that gaining weight is the result of too many calories overall. Another important fact of metabolism is that our bodies do not stop working, even when we are sleeping! Hearts are beating, blood is circulating, lungs are functioning, brains are even working. This all takes energy -- meaning we are still burning calories. The time of day you eat has nothing to do with weight gain.

More to the point, it's the type of foods you tend to eat late at night. Favorite foods for after-dark munching include ice cream, potato chips, chocolate, desserts -- you get the picture. Your body does not process food differently after dark, but nighttime tends to be the most sedentary time of the day, when your calorie needs are minimal. The bottom line: Eating after dinner tends to pack on the pounds. You can have that snack, but make it fruits and veggies.

4. Drink at least 8 glasses of water a day

We need to drink eight to ten glasses of water per day to be healthy is one of our more widely-known basic health tips. But do we really need to drink that much water on a daily basis? Some nutritionists insist that half the country is walking around dehydrated. We drink too much coffee, tea and sodas containing caffeine, which prompts the body to lose water, they say; and when we are dehydrated, we don't know drink enough.

The origins of the glasses per day figure are hard to put a finger on. Some say the number was derived from fluid intake measurements taken decades ago among hospital patients on IVs; others say it's less a measure of what people need than a convenient reference point, especially for those who are prone to dehydration, such as many elderly people.

Kidney specialists do agree that the 8-by-8 rule is a gross overestimate of any required minimum. To replace daily losses of water, an average-sized adult with healthy kidneys sitting in a temperate climate needs no more than one liter of fluid, about four 8-ounce glasses. According to most estimates, that's roughly the amount of water most Americans get in solid food. In short, though doctors don't recommend it, many of us could cover our bare-minimum daily water needs without drinking anything during the day.

Doctors from a wide range of specialties agree: By all evidence, we are a well-hydrated nation. Furthermore, they say, the current infatuation with water as an all-purpose health potion; tonic for the skin, key to weight loss is a blend of fashion and fiction and very little science.

Additionally, the idea that one must specifically drink water because the diuretic effects of caffeinated drinks such as coffee, tea, and soda actually produce a net loss of fluid appears to be erroneous. The average person retains about half to two-thirds the amount of fluid taken in by consuming these types of beverages, and those who regularly consume caffeinated drinks retain even more: Regular coffee and tea drinkers become accustomed to caffeine and lose little, if any, fluid. The same goes for tea, juice, milk and caffeinated sodas: One glass provides about the same amount of hydrating fluid as a glass of water. The only common drinks that produce a net loss of fluids are those containing alcohol and usually it takes more than one of those to cause noticeable dehydration, doctors say.

The best general advice is to rely upon your normal senses. If you feel thirsty, drink; if you don't feel thirsty, don't drink unless you want to. The exhortation that we all need to satisfy an arbitrarily rigid rule about how much water we must drink every day, it turns out, is an urban legend in search of a cheap magic bullet.

5. Fresh is always better than frozen

The vitamins and nutrients in fresh fruits and vegetables break down over time as they are exposed to light and air. Considering that some produce arrives at the grocery store up to two weeks after harvest, and often sits on the shelf for some time thereafter, frozen produce can actually be better than "fresh" in some cases. In addition, fresh produce may be improperly stored in transit and in-store, resulting in lost vitamins. Frozen produce: it's generally processed and flash-frozen close to the source of harvest, retaining its nutrients.

When buying fresh produce, look for what's in season and locally grown, as these selections will be freshest and relatively high in nutrients. Buy your not-in-season produce frozen to keep a good variety of fruits and vegetables in your diet while not compromising nutritional value.

When you compare fresh versus frozen vegetables, find out when vegetables are in season in your part of the world. That's when you want to buy fresh over frozen. If possible, always buy from a farmer's market that sources its produce from local growers. The less time your vegetables have spent in transit, the fresher and riper they'll be.

5 Tips for choosing fresh or frozen:

1. If you're making a special dish and it calls for a vegetable that is not in season in your part of the world, choose frozen over fresh.
2. Frozen vegetables are often not as rich in taste as fresh vegetables are, and the texture is a little different. If you or the people you're serving have a preference, shop accordingly. For example, frozen mushrooms tend to be tasteless and frozen broccoli tends to be tough.
3. When buying frozen vegetables, choose items with the "U.S. Fancy" label over the "U.S. No. 1" or "U.S. No. 2." That way you know you'll be getting the vegetables of the best size, shape and color. Also avoid any frozen vegetables with ingredient lists that include sugar, salt or anything else. The only ingredient should be the vegetable itself.
4. When you compare fresh versus frozen vegetables, take into account how much space you have available in your refrigerator and your freezer, and how long before you're going to use them.
5. Shop for vegetables with your budget in mind. Vegetables that are in season are cheaper than those that are not, as they're more plentiful and have less distance to market.

6. Eating turkey makes people especially drowsy

Not really, but this myth is based on fact. Turkey does contain tryptophan, an amino acid which is a natural sedative. But tryptophan doesn't act on the brain unless it is taken on an empty stomach with no protein present, and the amount gobbled even during a holiday feast is generally too small to have an appreciable effect. That lazy, lethargic feeling so many are overcome by at the conclusion of a festive season meal is most likely due to the combination of drinking alcohol and overeating a carbohydrate-rich repast, as well as some other factors:

Two other factors that contribute to the desire to sleep at the dinner table are meal composition and increased blood flow to the gastrointestinal tract. Studies have shown that a solid-food meal resulted in faster fatigue onset than a liquid diet. The solid-food meal also causes a variety of substances to jump into action that ultimately leads to increased blood flow to the abdomen. This increase in blood flow and an increase in the metabolic rate for digestion can contribute to the "coma."

Those who still feel wary of turkey's purported sleep-inducing properties should find solace in the knowledge that many items we eat contain tryptophan. Milk, beef, and beans are among the foodstuffs which house this amino acid, and experts say the average serving of chicken or ground beef contains as much tryptophan as a serving of turkey does.

7. Chewing gum takes seven years to pass through your digestive system

The gum component itself is pretty indigestible, but will "pass" in a mass and will not stick your insides together, either. This one probably got going when exasperated parents tired of buying more gum after half an hour because their kids had chomped, then swallowed, their allotment. Also, swallowing gum was seen as ignorant and lower class.
If you are like me, you were warned as a child, most likely by your Auntie or Grandma, that you shouldn't swallow chewing gum because it stays in your digestive system for seven years. Thank goodness, it is not true.

The human digestive system is built to dissolve and excrete what we put in our mouths in a matter of hours, days at most, but certainly not years. This is due to the effectiveness of your digestive system. When you swallow food, it travels down your esophagus into your stomach. Here enzymes and acids go to work on the food, beginning the process of breaking the food down. From the stomach, the partially digested food is moved into the intestine, where -- with help from your liver and pancreas -- the food is broken down into its components. These components are used to fuel the body. Those elements of food that can't be used are sent to the colon, where they'll be processed into waste.

Generally, gum is made up of four general components, and our bodies can easily break down three of these. The gum's flavorings, sweeteners and softeners are all no match for human digestion. It's the gum base that (sorry) sticks around. Gum base is made mostly of synthetic chemicals, and these chemicals give gum its chewy property. It's designed to resist the digestive properties of the saliva in your mouth. But once it's swallowed, even the gum base is subjected to the same treatment as regular food, and after it's recognized as useless by your digestive system, it goes the same route as any waste product.

The origin of the gum-swallowing urban legend is much less clear. Despite the good health of those who swallow gum, this rumor persists. It's OK to swallow the occasional watermelon seed, too. Doctors are pretty sure watermelon seeds do not grow into full-fledged watermelons.

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