Nutrition & Physical Activity
There is a lot of conflicting information about the pros and cons of supplements, so thanks for asking an important question. A healthy and nutritious diet involves six classes of nutrients:
Carbohydrate, fat, and protein are considered macronutrients [because our bodies require them in large quantities (grams/day)] and they yield energy. Vitamins and minerals are considered micronutrients [because our bodies need them in smaller amounts (milligrams or micrograms/day)] and instead of yielding energy, they help our bodies carry out necessary and important physiological processes. About 40 of these nutrients are essential for life because our bodies cannot synthesize enough to meet physiological needs (so our diet provides us with the bulk of these essential nutrients).
Vitamins are either water-soluble (water is required for absorption and are excreted in urine) or fat-soluble (requires fat for absorption and are stored in fat tissue). There are 9 different water-soluble vitamins: vitamin C and the eight B vitamins (thiamin, riboflavin, niacin, vitamins B6 and B12, folate, biotin, and pantothenic acid); and, 4 different fat-soluble vitamins: vitamins A, D, E, and K. Each of these vitamins have unique roles and functions in our bodies. For example, vitamin A promotes eyesight and helps us see in the dark, and vitamin K helps blood to clot.
Minerals are categorized as major or macro- (calcium, phosphorus, potassium, sodium, chloride, magnesium, and sulfur), and trace or micro- (iron, iodine, zinc, chromium, selenium, fluoride, molybdenum, copper, and manganese) minerals, the former needed in quantities of 100mg/day or more, and the latter required in much smaller, or "trace," amounts. These 16 essential minerals also play vital roles in the body, such as calcium in osteoporosis prevention and iron in (iron-deficiency) anemia prevention; and, they can be found in the body dissolved in body fluids as ions and/or are part of important compounds, such as calcium and phosphorus in hydroxyapatite found in bones and teeth. Other minerals, such as lead, are contaminant minerals and not nutrients because they can cause harm by disrupting normal bodily functions and processes, i.e. lead poisoning.
Vitamins ("vita" = life and "amine" = containing nitrogen) are organic (containing carbon, which is an element found in all living things) compounds (containing atoms of one or more different elements). Minerals are pure inorganic elements (containing atoms of the same element), meaning they are much simpler in chemical form than vitamins. All vitamins are essential or required by our bodies, whereas only some minerals are essential nutrients. Vitamins are vulnerable to heat, light, and chemical agents, so cooking, food preparation, processing, and storage must be appropriate to preserve vitamins in food. Minerals, on the other hand, are more stable to food preparation, but mineral loss can occur when they are bound to other substances in foods (such as oxalates found in spinach and tea, and phytates found in legumes and grains), making them unavailable for the body to utilize.
There is not a lot of research to state unequivocally if taking extra vitamins or minerals is harmful or helpful for the body. Our bodies do have a natural maximum capacity for different types of vitamins and minerals, so taking a lot of supplements may result in nausea or other side effects as your system works to get rid of the excess. While some vitamins and minerals are water soluble and can be excreted through urine if they are in excess, others are absorbed in fat and can accumulate over time. Some supplements can also interact with prescribed medications, so you may want to include them when asked about any medications during medical exams. You may also want to speak to your health care provider before adding any new supplements to your diet.
Health care professionals do agree that the best source of both macro and micro nutrients is from a well-balanced diet. Try visiting ChooseMyPlate.gov for information on the health benefits, nutrients, and vitamins available in different foods. Depending on the person, current levels of vitamins and minerals may be higher or lower than necessary and may warrant a supplement or dietary changes. To understand what vitamins and minerals are most appropriate for you, you may want to consult with your health care provider or a registered dietician. If you’re a Columbia student, you can make an appointment by contacting Medical Services (Morningside) or the Student Health Service (CUMC) to speak with either a health care provider or dietitian. You might also want to check out the get balanced! Guide for Healthier Eating. The National Institutes of Health (NIH) or the U.S. Food and Drug Administration (FDA) websites have additional information about dietary supplements in general.
Here’s to finding the balance that’s right for you!
Dear Confused by the news,
While this sounds like such a simple question, it's really not. First, what is ideal? The amount of calories needed to maintain each individual's weight appropriate for optimal health? The amount a person needs to maintain an unnaturally thin weight that meets false societal ideals? The amount an athlete needs to perform at her/his best? Reality tells us that the ideal caloric intake is different for everyone.
Caloric needs depend on age, gender, height, present weight, body frame, physical activities, hormones, and weight plans (maintain, gain, lose, etc). An intake between 1200 and 1400 calories per day is considered a low intake. This calorie level is just able to meet what are called basal metabolic needs, or the calorie needs to keep the heart beating and all the internal organs working. Calorie levels below 1200 should be avoided, because they may decrease metabolism and are usually hard to follow for any length of time. Very low caloric intake may promote binge eating due to the feeling of deprivation, and may be deficient in one or more nutrients. Some liquid diets call for fewer than 1200 calories, however, their long-term effectiveness is controversial, and they should only be followed under the supervision of a physician.
The Daily Values (DVs) used on food labels base their nutrient intake on a 2000 calorie per day diet. This was a result of many long meetings with nutrition experts who concluded that 2000 calories was the average amount needed by American adults. Therefore, short, thin females who are not active, will have caloric needs below 2000. For those who are "average" size and get moderate activity, caloric needs to maintain weight should be about 1600-2400 per day.
Instead of just worrying about a number of calories, have you tried listening to your own internal needs? Have you set goals related to healthy eating? Consider a focus on maintaining a balanced eating plan that includes a strong base in whole plant foods (fruit, vegetables and grains) and eat a moderate amount of healthy fats. Also don't go overboard on eating food just because it is fat-free (i.e. a whole box of "fat-free" cookies). Although fat calories are most easily converted to fat in the body, all calories from fat, carbohydrate and protein count! Finally, don't forget food should bring some pleasure to life and serves many needs other than energy functions.
If you would like to explore your individual caloric needs, or have other nutrition questions, Columbia students can make an appointment with the nutritionist at Medical Services (Morningside) or at the Student Health Service (CUMC). Columbia students may also want to check out Get Balanced! for tons of nutrition resources and information, including th Guide to Healthier Eating. You can also review many options and create your own plan using the online resources at MyPlate. Have fun determining the right balance for you and your goals. Remember to try new foods and new food cominbations — there are lots of healthy and tasty options. Eat and be well!
Dear Fat swimmer,
Swimming can be a wonderful form of exercise. It uses almost all the major muscle groups, and places a vigorous demand on your heart and lungs. It develops muscle strength and endurance, and improves posture and flexibility. The buoyancy factor makes it especially useful for people who are pregnant, have injuries such as leg or lower back problems, or who find high-impact exercise uncomfortable. It is a great sport for people of all ages and all proficiency levels. In order to lose weight, you might want to keep your swimming regime (speeding up your pace a little bit and increasing the length of your swimming sessions, if necessary), and supplement it with some good-paced, arm-swinging walks.
Research on swimming and weight loss, however, has produced inconsistent and contradictory results. Studies have found that swimmers lost weight (and body fat), gained a few pounds, and had no weight changes at all. In most of the cases where swimmers gained weight, it was lean body mass (muscle) and not fat.
One study found that people who swim in cold water may consume more calories post-workout than people who swim in warmer water. So if you're swimming primarily to lose weight, make sure that you aren't inadvertently consuming unneeded calories during post-workout snacks and meals. In addition, the number of calories you burn while swimming depends on how fast you go and for how long. At a slow pace, twenty laps may burn only fifty calories — little more than simply staying afloat. On the other hand, a swimmer doing a brisk forward crawl will often burn as much as eleven calories per minute.
Swimming in a pool may be more conducive to the type of workout you're looking for than swimming at a beach or lake; pools often have lap swim hours, and you won't have to contend with rolling waves or boats. If you're in New York City, check out one of the free lap-swim pools maintained by the city. For a guaranteed workout, you can also join up with a United States Masters Swimming group near you.
In the end, weight loss is dependent on a simple formula; more calories are burned than are consumed. No one exercise is necessarily better than another for weight loss; what matters is that you eat a healthy, well balanced diet and remain regularly physically active. Swimming can be a fun activity to add to your workout routine, whether you're a novice or a master. Enjoy!
Creatine is a substance manufactured in the human body by the liver and kidneys or obtained from meat in the diet. It is present in muscle, nerve, and sperm cells. In muscles, creatine is used to form phosphocreatine, which can be used to supply energy needed for muscle contractions. It has been suggested that by increasing creatine in the diet, one may increase the amount of phosphocreatine in the muscle, which would then provide a greater availability of high energy phosphate for energy production during muscle contraction. It also may cause the muscles to retain water, a proposed mechanism for the "bulking" effect of the supplement.
No one really knows how much creatine is too much. Some people experience muscle cramps, electrolyte imbalances, fever, or gastrointestinal symptoms like nausea and diarrhea when they take creatine. Long-term effects are much less well-studied. While there is little conclusive evidence for adverse affects, people who have liver or kidney problems or who take diuretics should avoid taking creatine because of the theoretical complications. People with diabetes or who take either medications or supplements that affect blood sugar should also use caution. If you start to notice any side effects, you should stop taking creatine and see your health care provider.
As for benefits, creatine can enhance performance for short bursts of anaerobic activity, like weightlifting. However, people doing aerobic activities, like running or cycling, probably won't see any improvement.
The amount taken in through commercially marketed supplements is far greater than one would be able to ingest via food. Some regimes call for a loading period — perhaps 20 to 25 grams for five days, followed by daily doses of about 5 grams. Non-meat eaters (vegans) may respond better since their natural creatine stores are probably lower than meat-eaters. Since any long-term effects from these high levels are uncertain, your best bet is to let your health care provider know that you take creatine. That way, if you ever do experience side effects, he/she will be better able to help you decide whether to keep pumping up.
Dear Cow lover,
Why does a milking stool have only three legs? Because the cow has the udder! Get it? Unfortunately, there’s not such a definitive answer to YOUR question. Research on the health effects of drinking milk has produced mixed results. As with any other food group, it is important to consider the pros and cons of dairy consumption.
Before a discussion of pros and cons, here is a run-down on recent milk research as it relates to osteoporosis. Although it is thought that drinking milk every day helps ward off osteoporosis, a small group of renowned researchers recently found that drinking too much milk can actually contribute to calcium loss. This is because the high amount of protein in milk thins blood and tissue, causing it to become acidic. In order to neutralize the acidity, the body draws out calcium from bones. As a result, the more milk you consume, the more calcium you need to process the protein intake. With that being said, drinking moderate amounts of milk each day (500 to 700 milligrams daily) is still thought to be good for your bones. More information on osteoporosis can be found in Calcium, milk, and osteoporosis?.
Moooving on, here is a list of the various pros and cons of drinking milk:
- Milk is high in calcium, which is important for healthy bones. Additionally, the calcium in milk is well absorbed by the digestive tract because the vitamin D and lactose found in milk facilitate calcium absorption. Still, it's possible to get ample calcium without drinking dairy milk — by eating foods such as tofu, soy milk, or greens such as kale. See Calcium — how much is enough? for more information.
- Whole milk is brimming with protein, which is beneficial for muscle growth.
- Studies have shown that drinking milk can help regulate weight gain.
- Skim milk is very low in fat and cholesterol, and is a complete source of protein.
- Milk is also a good source of phosphorous, magnesium, vitamin A, vitamin D, and riboflavin (a B vitamin).
- Whole milk is high in saturated fat, which can increase cholesterol level.
- Milk is a common cause of food allergy (allergy to milk protein).
- Many people lack the enzyme to digest lactose (milk sugar). This is called lactose intolerance, which causes bloating, gas, and diarrhea.
- Milk may contain the antibiotics given to the cow while it is lactating. It has been argued that humans subsequently absorb these antibiotics upon drinking milk, potentially leading harmful bacteria to become more resistant to these antibiotics. As a result, when antibiotics are prescribed, they may not be as effective at killing the bacteria.
- Some research has found a correlation between drinking milk that is produced by cows injected with the bovine growth hormone (rBST) and cancer. However, research shows highly mixed results.
As a side note, if you are concerned about the possible effects of antibiotics and rBST on your body, it is possible to buy antibiotic-free (and typically hormone-free, as well) milk from specialty grocers that carry natural foods. Alternatively, you can purchase USDA-certified organic milk, which is available at most supermarkets.
Overall, when researching the pros and cons of milk, it is important to take into account that there are two opposing sides — one that believes that milk is great for the body, and another that believes that milk does not aid against osteoporosis and is even harmful for the body. Whatever camp you choose to join, it is important to be informed. Seize every opportunity (to obtain information), and milk it for all its worth!
There is a bit of debate about the pros and cons of olive oil vs corn oil. Some newer research suggests when included in a well-balanced diet, corn oil may have comparable or possibly greater, health benefits when juxtaposed with olive oil. Both corn and olive oil are made up of mostly unsaturated fats. Monounsaturated fats and polyunsaturated fats are often described as “healthy fats”. Research suggests that these two types of fatty acids may help lower cholesterol, normalize blood clotting, and also possibly improve insulin and blood sugar levels — and they are healthier choices to cooking with butter or lard. Good vs. bad fats can provide some more detailed information about the different types of fat found in food.
Olive oil has a higher percentage of monounsaturated fats when compared to corn oil. The exact ratios are as follows:
- Corn oil: 59% polyunsaturated 24% monounsaturated 13% saturated, which give a 6.4:1 unsaturated/saturated fat ratio
- Olive oil: 9% polyunsaturated 72% monounsaturated 14% saturated, which gives a 5.8:1 unsaturated/saturated fat ratio
For quite some time monounsaturated fats were credited with lessening the hardening of arterial walls and thus reducing risks of heart and kidney disease. Recent clinical studies seem to lean more heavily towards the positive impact of polyunsaturated fats over monounsaturated fats in protecting against heart disease.
Also of note when cooking with oils, corn oil tends to be more stable at higher heats, whereas olive oil is more stable at lower heats and tends to burn at high heats. So, depending on your recipe, one may be more suitable on the stove than the other.
Olive oil also has the most nutritional value when it is freshest, according to researchers. As soon as olive oil is exposed to air and light it begins to degrade and lose its heart-healthy benefits. While many of us are accustomed to expiration dates on bottles and cans, olive oil can also have both an expiration date and a harvest date — checking for those is advised by industry leaders. Olive oil enthusiasts and experts suggest using oil within about six months of harvest, if possible. When you store olive oil between uses, try to keep it in a cool environment away from light.
When shopping for corn oil, some consumers may be concerned with finding sources that are free of genetically modified organisms (or GMO-free). Corn is one of a handful of crops that are more likely to be genetically engineered than others. To learn more about GMO debate, check out GMO’s — okay for consumption?
While the existing research on olive and corn oil has certainly shaped nutritional recommendations we may have heard for years, it’s also worth noting that even clinical studies have limitations. And just like the evolving understanding of monounsaturated fatty acids vs. polyunsaturated fatty acids, what we know about olive oil and corn oil today may evolve with new research and deeper understandings of how these oils play a role in our bodies and health.
Perhaps equally if not more important than the type of oil itself, is what you are sautéing, dressing, or marinating. Eating a well-balanced diet in addition to choosing dishes and snacks with healthy fats may make the bigger impact on overall health. Some research suggests that diets with an emphasis on vegetables, fruits, legumes, and whole grains (and less emphasis on meat, poultry, and dairy) when partnered with healthier fats from sources like nuts, corn oil, and olive oil can promote heart health and lower cholesterol.
If you are looking for more individualized advice on diet and nutrition, you may want to speak with a registered dietician, or a health care provider. If you’re a Columbia student, both the Morningside campus Medical Services and the Student Health Service on the Medical Center campus have registered dieticians on staff for nutritional consultations. You can also access nutritional information through Alice! Health Promotion Nutrition Initiatives.
Here’s to good eating and good health!
Many people experience a side stitch, which is a sharp pain in the side of the abdomen, when they exercise. The exact cause of these side stitches can vary from person to person. This condition, technically referred to as exercise-related transient abdominal pain, is often associated with a muscle spasm in the diaphragm. Some research indicates that the amount of food eaten prior to exercising may influence the occurrence of side stitches.
Side stitches can occur with any type of exercise, but seem to be most commonly associated with jogging and running. Some of the following tips may to help lower the frequency at which side stitches occur:
- Delaying exercise or activity for a longer period of time after eating, if your side stitches occur when you exercise after eating.
- Sticking to long, low intensity workouts, instead of quick, high intensity ones.
- Warming-up and gradually picking up workout pace may help prevent side stitches, regardless of exercise intensity.
- Building stretches of speed intervals into your workout in order to strengthen your abdominal muscles and diaphragm. Some believe weak abs and diaphragms cause side stitches so making them stronger may help to prevent side stitch occurrences.
- Continuing to work out at an even pace; some researchers found that people with better aerobic fitness tend to get fewer side stitches. Therefore, the more you build up your endurance and cardiovascular fitness, the less likely you are to wind up with a side stitch.
- Avoiding shallow breathing; instead taking slow, deep breaths during exercise.
If these prevention strategies fail to help, and you do get a side stitch, slowing down and breathing deeply is one way to alleviate the pain. Two other things you can try are: (1) bending over while tightening your stomach muscles a few times; and, (2) applying pressure to the area with your fingers, giving yourself a sort of "pressure massage" where the pain is. For this, try pushing your fingers deeply into your stomach in a spot just below your right ribs, while pursing your lips and exhaling as hard as you can. Simply grunting loudly while breathing out may also help, as could slowing down until the pain is gone.
Occasionally, side stitches might come from an allergy or intolerance to wheat or dairy products. Side stitches may occur up to 24 hours after eating or drinking something that contains this product. To see if this applies to you, you might want to keep record of your meals, snacks and physical activities and see if your side stitches occur after eating a specific food or food group. Side stitches may also be mistaken for pain in the heart caused by lack of oxygen. If the pain comes from under the breastbone, or radiates down your left arm, makes you out of breath and comes from exercise or strenuous physical activity, your best bet would be to see a health care provider as soon as possible.
Hopefully, following the tips above and listening to your body will ensure that most of your stitches come only after those hysterical jokes.
As vegetarianism, veganism, and even just eating less meat become more popular dietary and lifestyle choices for a growing number of people, adequate protein sources are always a topic of discussion. There have been scores of arguments about protein in all its facets: how much you need, what kinds are most useful to the body, and how to prepare it. But what it comes down to is: every body is different, has different needs, and digests foods uniquely, so the best non-meat sources of protein for one person might be the worst for someone else.
The recommended daily protein intake for healthy adults is about 0.4 grams per pound of body weight. Vegans (those who avoid all animal products, including dairy and eggs) may require a bit more at 0.5 grams per pound of body weight. Protein facilitates growth, metabolism, immune system functioning, repair, muscle contraction, and the transmission of nerve impulses and hormones in the body. It can also be a source of energy when the body runs out of carbohydrates and fat for fuel. And protein's not that hard to find, even for vegetarians. Almost every food contains protein: nuts, seeds, beans, soy products (tofu, soy milk, tempeh), grains (wheat, oats, rice), eggs, and dairy products all being excellent vegetarian sources (many of which tend to be low in saturated fat, cholesterol, and sodium).
The list below gives the protein content of some of the highest protein and/or most popular vegetarian foods:
- Tempeh — 1 cup — 31 g
- Lentils — 1 cup — 18 g
- Chickpeas — 1 cup — 15 g
- Tofu (firm) — 4 oz — 11 g
- Peanut butter — 2 tbsp — 8 g
- Soymilk — 1 cup — 7 g
- Soy yogurt — 1 cup — 6 g
- Whole wheat bread — 2 slices — 7 g
- Broccoli, cooked — 1 cup — 4 g
Protein is a macronutrient made up of smaller parts, called amino acids. There are different amino acids, many of which the body can produce, but nine which the body cannot. These nine must be eaten, and are therefore called essential. Animal proteins contain all nine of these essential amino acids in appropriate proportions, while the proteins found in plants often do not. Plant-based sources of protein have various amounts of amino acids in them. As such, it was previously thought that certain ‘complimentary proteins’ or combinations of plant-based proteins were needed in order to get all essential amino acids. However, rather than planning specific food combos at each meal, eating a variety of plant-based proteins over the course of a day should ensure that you get the essential amino acids you need.
You might find it helpful to consult with a registered dietitian if you want a more specific evaluation of your diet and unique nutritional needs. Columbia students can contact Medical Services (Morningside) or the Student Health Service (CUMC) to schedule an appointment. There is also a wealth of information online about vegetarian recipes, philosophies, and nutritional facts about specific foods.
People decide to eat less meat or no meat for myriad reasons that include health, animal rights, environmental sustainability, and religion. You can rest assured that your decision will further any or all of these goals without depriving you of the protein you need. Enjoy!
Parched after a workout, a person might be tempted to grab the nearest sports drink to help rehydrate and reenergize. In fact, water is the best option for most people post-exercise. Your body depends on water to sustain chemical reactions and to maintain correct body temperature. It's possible to lose up to a quart of water during an hour of exercise through sweating, which can lead to dehydration if fluids aren't replaced. Drinking water before and during exercise also has benefits for performance.
Here are some tips for healthy hydration:
- Consume 20 ounces of water during the two- to three-hour period before you start exercising.
- Consume 8 ounces of water during your warm-up.
- For every 10 to 20 minutes of activity, drink 8 ounces of water.
- Within 30 minutes of finishing your activity, drink 8 ounces of water.
- For every pound of body water you lose during exercise, drink 16 to 24 ounces of water.
- Drink cool water as it is more quickly absorbed by your body than warmer water, and it is less likely to cause cramps.
- Avoid drinks that contain caffeine, a diuretic. They can also cause the jitters and shakes.
- Steer clear of alcohol, also a diuretic. In addition, it is a poor energy source, and can depress the heart and nervous system. (Obviously, alcohol also hampers your coordination and impairs performance.)
- Make hydration a part of your daily routine.
If you are an endurance athlete and workout for longer periods of time (more than 45 minutes), you may want to opt for a sports drink to fuel your muscles and replace electrolytes (such as salt) that are lost in sweat. There are many brands and flavors and several low-sugar energy drinks have recently been introduced to the marketplace. If the taste of these drinks is too strong for you, consider diluting them with cool water.
As always, listening to your body is good advice when it comes to hydration. Unfortunately, thirst alone is not a good indicator of how much you need to drink, because thirst is quickly quenched by drinking very small amounts of water; additionally, once you notice thirst, you are already on your way to dehydration. An easy way to check your hydration level is to notice the color of your urine. If it's a dark yellow or orange color, you could probably use some plain old water. A hydrated body excretes nearly clear-colored pee (although taking certain vitamins or supplements may turn your pee darker in color).
Remember, these tips for hydration apply to any kind of activity and you don't have to be a marathon runner to benefit from quenching your thirst. Stay hydrated, have fun, and good job with those workouts!
Dear The hulk-ette,
You've touched on two commonly misunderstood components of exercise. Despite what all the late night infomercials tell us, fat and muscle are two distinctly different tissues and one can't be turned into the other. Muscle will always be muscle and fat will always be fat. As to the second thought you mentioned, one pound of either is exactly that — one pound.
It is indeed a myth that fat cells can change into muscle. You can burn fat and build muscle, but a fat cell will never turn into a muscle cell. Body fat is a storage place where our body puts extra energy when we consume more calories per day than we burn. If someone continues to consume more calories than s/he needs, the size of their existing fat cells increases. When we "burn fat" we are actually shrinking the size of our fat cells by using the energy that has been stored there. There are also have a fixed number of muscle cells so when we are building muscle the individual muscle cells are increasing in size (bulking up).
Over time, you can gain muscle mass through a variety of activities including weight lifting and other forms of resistance training. If your main goal is to bulk up, you are likely increase your muscle mass which could increase your overall weight. Remember that your weight also depends on what you eat and if you're doing other types of exercise. For example, if you're doing lots of cardio, then you may ultimately lose fat and decrease your weight.
Instead of stepping on a scale, you may want to consider measuring your body composition. Methods to assess body composition (lean body mass vs. fat body mass) can help give you a more accurate idea of what comprises your body. The related Q&As below contain many useful tips to guide your training.
You can always talk with a Registered Dietitian (RD) or a trainer to help determine the weight and exercise plan that's right for you. At Columbia, nutrition appointments are available by calling x4-2284 or logging in to Open Communicator, and personal trainers are available at Dodge Fitness Center. You can also join the CU Move initiative, Columbia's online physical activity program. CU Move encourages members of the Columbia community to engage in active lives that include regular physical activity. The program provides participants with motivation and incentives to be active throughout the year. If you are not a student at Columbia, check with your local fitness center or health care provider for nutrition and exercise referrals.
Choosing to be active can help you feel better now and for years to come — thanks for helping us bust some common exercise myths.