A calorie is the standard unit for measuring energy released from energy-yielding nutrients, such as fat, protein, and carbohydrate. Fat is an essential nutrient that helps the body transport and absorb fat-soluble vitamins (e.g., A, D, E, and K), among other functions. Whereas proteins and carbohydrates have only four calories of energy per gram, fat has nine. Food labels are federally standardized to help make it easier for the consumer to know what's in a particular food. You can calculate the percentage of calories from fat by looking at the column marked "Percent Daily Value" for total fat and simply add up these percentages. It's recommended that fat make up no more than 30 percent of your daily diet (meaning less than or equal to 30 percent of total calories a day from fat).
Although it is important to watch both calories and fat grams, it's best to focus on the total number of calories consumed, which often seems to be forgotten. With the introduction of low-fat and fat-free versions of many common foods, you'd expect people to lose weight. Instead, many are either staying at the same weight or even gaining weight. Sometimes you can eat more of these foods than their full-fat versions for the same number of calories. However, sometimes low-fat foods contain more sugar than their full-fat cousins, and hence as many calories per serving. Ultimately, if you eat more calories than your body expends, regardless of whether these calories come from fat, protein, or carbohydrates, you will gain weight. Unused energy is converted and stored as excess body fat.
The amount of calories a person needs is based on body weight, age, gender and physical activity level. Generally, 1200 to 1400 calories per day is considered low, and anything above 2400 is considered too much. To find out how many calories you should be getting a day, check out the MyPlate website. This USDA-sponsored site will ask you to input your age, gender, weight, height and physical activity level in order to determine what caloric intake will be right for you. You can also check out Ideal Caloric Intake? in the Go Ask Alice! archives for more information on calorie counting.
Dear Joyful Juicer,
Juicers can be a great low calorie, high nutrient, tasty treat. However, they don’t generally carry all the benefits of eating the original fruit or veggie from whence it came.
If you've made juice, you know that it takes a lot of fruit to make a container of juice. Usually, juicers extract the juice and some pulp from fruits and/or vegetables. You’ll get all of the vitamins, minerals, beneficial plant chemicals (phytochemicals), and carbohydrates in juice that's extracted from a whole fruit. However, you won’t get much of the fiber, and depending on the fruit, you may not get any of it.
Fiber aids in the digestive process. It acts sort of like a scrub brush for your intestines and speeds up the movement of waste through your system. It also can fill you up, and may help protect against certain cancers. Fiber in fruit is found in the membranes between sections, the white part around the outside (as in oranges and grapefruits), the seeds, the skin, and the peels. For example, orange juice contains no fiber (even if it has pulp) because the fiber is found in the membrane, which is lost during the process of juicing.
It is also important to remember that juice is not a low calorie drink. An eight ounce glass of orange juice contains 110 calories — the equivalent of two oranges (each contains about 60 calories). But you won't feel as filled up from juice since it doesn't contain any fiber. For many people, drinking a caloric beverage, such as juice, isn't as satisfying as eating the same amount of calories in food. For those who need to increase caloric intake — such as athletes, children, or teens — juice is a great choice.
Fresh juice is certainly tasty and an excellent source of many nutrients. Less stable vitamins, such as vitamin C, are not compromised in fresh juice as they may be in some processed varieties. Also, watch for added sugar in many processed juices that can increase caloric content.
In general, juice is just fine. But if fiber’s what you’re after, go for the whole fruit or veggie over the liquefied form. Happy juicing!
Vitamin A is an essential, fat-soluble vitamin that has many diverse benefits for humans. Vitamin A promotes eyesight and helps us see in the dark; aids in the differentiation of cells of the skin (lining the outside of the body) and mucous membranes (linings inside of the body); helps the body fight off infection and sustain the immune system; and, supports growth and remodeling of bone. In addition, dietary vitamin A, in the form of beta carotene (an antioxidant), may help reduce your risk for certain cancers.
Adequate vitamin A intake is essential to human health. Vitamin A deficiency can lead to night blindness (inability to see in the dark or to recover sight quickly after being exposed to a flash of bright light in the dark) and xerophthalmia (progressive blindness that becomes irreversible if not treated in time with vitamin A).
Vitamin A deficiency can also reduce the health and integrity of skin and other epithelial tissues. The effect on skin can result in dry skin and hyperkeratosis (the development of clumps of skin around hair follicles). The effect on epithelial tissues can negatively affect the digestion and absorption of nutrients and cause infections of major systems and their organs (i.e., gastrointestinal, nervous/muscular, respiratory, and urogenital). In addition, bone growth can stop and normal bone remodeling can become impaired, resulting in anemia and weakened immunity.
The Recommended Dietary Allowance (RDA) for vitamin A is measured in retinol equivalents (RE), retinol being the active form of vitamin A. For adult men, the RDA is 900 micrograms of RE per day and for adult women it is 700 micrograms of RE per day.
Despite its benefits, too much Vitamin A can cause toxicity, the effects of which can vary depending on its source. Excessive intake of vitamin A in dietary form is not harmful, but will cause one's skin to turn yellow in color. In contrast, large dose supplements (10 - 15 times the RDA) of vitamin A (as retinol) is harmful, and could result in the development of a fatty liver (hepatomegaly), dry skin, nausea, vomiting, fatigue, weakness, headaches, anorexia, and/or possibly increase the risk of birth defects among pregnant women. Symptoms depend upon whether or not vitamin A intake was taken over a long period of time (chronic) or a single excessive dose at one point in time (acute). In general, fat-soluble vitamins should not be consumed in excess of the recommendations because, unlike water-soluble vitamins in which the excess is excreted out of the body, an excess of fat-soluble vitamins will be stored and accumulated in the body.
It is highly recommended that vitamin A be consumed in the diet rather than from supplements. The richest sources of dietary vitamin A are liver, fish liver oils, milk, milk products, butter, and eggs. Liver is an especially rich source because vitamin A is primarily stored in the liver of animals and humans. Vitamin A is also found in a variety of dark green and deep orange fruits and vegetables, such as carrots, sweet potatoes, pumpkin, spinach, butternut squash, turnip greens, bok choy, mustard greens, and romaine lettuce. Beta carotene is the most active carotenoid (the red, orange, and yellow pigments) form of vitamin A. In addition, cooking (but not overcooking) increases the bioavailability of carotenoids in plant foods and absorption of dietary vitamin A is improved when consumed along with some fat in the same meal.
Hope this helps,
Dear Breakfast Boycotter,
Your brain (and central nervous system) run on glucose — that's the fuel you need to think, walk, talk, and carry on any and all activities. Let's say that the last time you eat something at night is at 10 or 11 PM (not optimal, just an example). The following day, you don't eat breakfast but wait until about noon or so to eat — you've gone thirteen or fourteen hours with nothing in your system. Your poor brain is surely deprived — and your body has to work extra hard to break down any stored carbohydrate or turn fat or protein into a usable form for your brain to function. That's a lot to ask for when you're sitting in a classroom, trying to concentrate on reading, or doing any other work. Eating breakfast has been proven (many times) to improve concentration, problem solving ability, mental performance, memory, and mood. You will certainly be at a disadvantage if your classmates have eaten breakfast and you've gone without. On average, they will think faster and clearer, and will have better recall than you. School or work can be tough enough without this extra added pressure.
Breakfast skippers also have a harder time fitting important nutrients into their diet. Many foods eaten at breakfast contain significant amounts of vitamins C and D, calcium, iron, and fiber.
Some people believe that skipping breakfast may help them lose weight. Not so! Skipping meals often leads to overeating later in the day. Becoming overhungry often leads to a lack of control and distorted satiety signals (meaning it's hard to determine when you're full). This can result in taking in more calories than if one had an appropriate breakfast. As a matter of fact, it's easier to control one's weight by eating smaller meals and snacks more frequently.
What if there's just no time in the morning to eat breakfast? There are plenty of items you can bring along with you to school or work. Carry a resealable bag of easy-to-eat whole grain cereal, or bring a yogurt or small box of skim milk, juice, or fruit. If you just can't stomach food in the morning, try to have a little something — such as some juice — and bring along a mid-morning snack. Other good portable items include: whole grain crackers, a hard boiled egg, cottage cheese, low-fat granola bars, or even a peanut butter sandwich. Single serving hot cereals, such as oatmeal, are handy — all you have to do is add hot water, available at most cafeterias or delis.
Whatever your choice, eat something. If you think you're doing fine with no breakfast, just try changing your tune for a week —you're likely to notice a difference. You will undoubtedly perform better with some fuel in your system, and, hopefully, become a breakfast believer.
It's a great idea to plan consciously when switching over to a vegetarian diet. Not eating meat can offer many health benefits, as well as addressing environmental and ethical concerns you may have regarding eating animals. However, before making the switch to a meat-free lifestyle, it is important to get a sense of the pros and cons.
Here’s the best news of all: with a well-planned diet, vegetarians can live a totally healthy lifestyle and help contribute to a better planet. The following list describes various benefits of vegetarianism:
- Plant foods are abundant in nutrients, including vitamins, minerals, and protein. They also contain phytochemicals — plant chemicals that are not essential to life, but may help protect against disease — such as beta-carotene. Eating a variety of colors of fruits and vegetables can help ensure that the benefits nature provides are reaped.
- Reduce your risk of type 2 diabetes. Vegetarians benefit from eating less saturated fat and cholesterol, and higher amounts of complex carbohydrates, dietary fiber, certain minerals, and phytochemicals. Cholesterol is only found in animal foods, so vegan diets are completely cholesterol-free.
- Contribute to the vegetarian cause! Whether you have aim to respect animals, lessen your carbon footprint on the environment, or just want to make a lifestyle change, as a vegetarian you are making your own positive impact on the world. You can be proud that you are living according to the beliefs that you stand for.
Whenever you cut a food group out of your diet, it is important to understand how to replace the vital nutrients that go along with it. While the positives are all fine and dandy, it is important to be aware of the challenges of being a vegetarian:
- It can be harder to get the protein you need. Protein is important formaintaining and repairing muscle tissue, and manufacturing blood cells, antibodies, hormones, and enzymes. Fortunately, there are plenty of non-meat proteins to supplement your diet.
- Possible vitamin and mineral deficiencies can develop without a balanced eating plan. Cutting out dairy, meat, fish, and poultry reduces your intake of vitamin B12 (important for nerve transmission and necessary for life), calcium (for strong bones, among other functions), iron (for blood), and zinc (for immunity and healing), just to name a few.
- Depending on where you live, it may be challenging to adhere to a meat-free lifestyle. For example, living in a big city may provide you with endless veggie options, while a small-town lifestyle may make it more difficult to find healthy substitutions for meat.
- You may have difficulty explaining your eating habits to family and friends.While it may seem that being a vegetarian is relatively mainstream, certain cultures leave little room for herbivores. You may encounter some sticky situations where people have prepared for you a meaty meal, or perhaps, your friends and family may challenge your decision to remain meat-free.
Remember, what is included in your diet (rather than what is excluded) is what counts. It is extremely important to incorporate a balanced eating plan full of nutrient-rich foods. For help in selecting a healthy eating plan appropriate for your state of health, age, size, activity level, preferences, and moral and ethical values, consult with a registered dietitian. Columbia students can make an appointment with a registered dietician at Medical Services through Open Communicator or by calling (212) 854-7426. Informed choices are the best choices!
February 23, 2012507783
Dear Confused and College Bound,
You are not alone with your concerns. Going to college is a big step in a person's life involving major changes. You and those around you may be living on your own for the first time, making decisions on a buffet of issues, including what to eat.
Eating healthy at college is possible. Many college dining services are offering more healthy choices and are often quite receptive to students' concerns and dietary preferences. But, this is only part of the challenge. In an environment where time, friends, and finances may combine in new ways, having options available only solves some of the puzzle. It's important to experiment with what works best for you. For example, that traditional idea of three square meals a day has been updated with a more contemporary concept of eating five smaller meals spread throughout the day. Steer clear of diets or fads, especially those that drastically limit a particular nutrient. Remember, balance, moderation, and variety win out over trendy and extreme. For some practical tips, navigate through the many options on Choosemyplate.gov. Columbia students can also take advantage of the resources from the get balanced! initiative. Plan ahead when possible so you don't have to rely on vending machines when you're hungry; think of ways to incorporate fruits, vegetables, and whole grains on a daily basis. Eating more of these will fill you up and possibly even enhance your already stellar brain power.
Making time for physical activity is important, too. Most college fitness centers have a variety of movement classes and options. When the weather is right, grab a friend and walk, run, bike, or blade outdoors. If you are Columbia affiliated, you can connect with the CU Move initiative. CU Move encourages members of the Columbia community to engage in active lives that include regular physical activity. The program provides participants with motivation, incentives to be active throughout the year, and event calendars with access to plenty of free and low-cost physical activity options on campus and around NYC.
Now, to address the second part of your question: an eating disorder, such as anorexia nervosa, is less about food, eating, and body weight. It has more to do with mental health, emotional, physical, socio-cultural, and family issues. If this is a particular concern of yours, you might want to take a look at Eating disorders vs. normal eating. Additionally, if you are a Columbia student, you can make an appointment with a health care provider or a registered dietitian to discuss your concerns by contacting Medical Services (Morningside) or the Student Health Service (CUMC).
Give yourself some time to adjust to a new environment and ask for help when you need it. Everything in moderation, even moderation.
Enjoy your time at college,
RDAs (Recommended Dietary Allowances), prepared by the Food and Nutrition Board of the National Academy of Sciences, have been around for over 50 years, with periodic updates. The RDA is the average daily dietary intake level that would adequately meet the nutritional needs of nearly all (98 percent) healthy persons. RDAs include nutrients for which there is sufficient scientific evidence that they are required for good health. Their intention has always been to establish "standards to serve as a goal for good nutrition." RDAs provide the basis for evaluating the adequacy of diets of population groups. They are set at a level that includes a safety factor appropriate to each nutrient; so, this level actually exceeds the requirement for most individuals.
The Food and Nutrition Board has established Dietary Reference Intakes (DRIs). In addition to RDAs, DRIs include recommendations for food components for which RDAs cannot be established. Some of these include fat, carbohydrate, fiber, and plant estrogens, among others. DRIs also include maximum intake levels. Three dietary intake reference values for DRIs are:
- Adequate Intake — the dietary intake level that would adequately sustain health when an RDA cannot be determined because of insufficient scientific evidence.
- Estimated Average Requirement — the estimated dietary intake level that would maintain the health of half of a specified age and sex group.
- Tolerable Upper Intake Level — the maximum level of daily nutrient intake that's apparently safe and unlikely to cause negative health effects in most healthy individuals.
DRIs and RDAs are not developed for specific individuals, but are for the making of policies for feeding programs, food labeling, and food fortification. The numbers signify levels of each compound that are appropriate for most healthy people in each category. To access information on RDAs and DRIs, check out the United States Department of Agriculture's (USDA) Food and Nutrition Information Center website.
Vitamin supplements may contain an amount equivalent to the RDA for DRI, but you'll probably not find a supplement with every imaginable nutrient, vitamin, and mineral. There are innumerable substances that keep us healthy, many of which cannot be packaged in a pill. In addition, many nutrients are difficult for the body to absorb when they come in pill form. Obtaining nutrients directly from a balanced diet of fruits, vegetables, whole grains, and lean proteins is still the recommended manner of giving your body all it needs to be healthy.
To assess whether your current diet is filled with nutrients, check out ChooseMyPlate.gov. You can also speak with your health care provider about whether you need a multivitamin or if the food you eat is sufficient. Students at Columbia can also make an appointment to speak with a registered dietician or a health care provider either through Medical Services (Morningside) or the Student Health Service (CUMC). Take care,
As they say, everything in moderation — including fiber! Eating enough fiber can have many health benefits, while too much may have consequences. By learning how much fiber you need, how much is in your food, and adjusting your diet accordingly, you’ll be able to strike a balance that’s ideal for your body (and your bowels).
Fiber is basically composed of plant-based food matter (fruits, veggies, whole grains, and legumes) that can’t be broken down by your digestive system. Whole foods contain both soluble (dissolves in water) and insoluble (does not dissolve in water) fiber. Although the recommendations below don’t distinguish between these two types of fiber, they are different and have distinct functions — soluble fiber helps to reduce cholesterol and glucose levels, and insoluble fiber helps with constipation by increasing fecal bulk.
Overall, fiber may lead to many health benefits, such as:
- Keeping you regular. Fiber decreases the risk of constipation by bulking up and softening your stool.
- Maintaining your bowel health. Fiber may prevent the development of diverticulitis and hemorrhoids. It has also been shown to reduce the symptoms of irritable bowel syndrome (IBS) in some cases.
- Lowering cholesterol and blood glucose levels. By reducing bad (LDL) cholesterol and blood glucose levels, soluble fiber also leads to a decreased risk for cardiovascular disease, coronary heart disease, and type II diabetes.
- Controlling your appetite/weight. Foods that contain fiber are typically low in fat, energy-dense, take more time to chew, keep you full for longer, and block some of the digestion of fats and proteins.
- Preventing cancer. Fiber consumption may lower the risk for colorectal cancer, but the evidence is not yet conclusive.
Curious if you are getting enough fiber in your diet? You can use either the USDA Food List or WebMD’s Fiber-o-Meter to figure out the fiber content of the foods you eat and get suggestions for high-fiber foods. Making a habit out of reading the nutrition facts on food labels will also help. Generally, women need less fiber than men, and those aged 51 years or older need less than younger individuals. The following table can give you an idea of how much fiber you need on a daily basis:
Age 50 or younger
Age 51 or older
Source: Institute of Medicine
However, having too much fiber in one's diet can cause problems. When the intake of fiber is too high, it can replace other energy and nutrients that you need in your diet. Some insoluble fibers bind certain minerals, including calcium, magnesium, phosphorous, and iron. Too much fiber can also cause abdominal discomfort, gas, and diarrhea, and block the gastrointestinal (GI) tract if you add too much fiber too fast. For some, fiber supplements may potentially cause additional, more severe side effects such as allergic reactions and asthma, gastrointestinal distress, and drug and nutrient interactions. If you feel that you might benefit from taking fiber supplements, it's best to speak with a health care provider first to make sure it’s right for you.
So, before you load up on fiber, try adding it to your diet gradually, so that your GI tract has time to adapt. You'll also want to drink lots of fluids to keep the fiber soft. Choosing a variety of soluble and insoluble fiber-rich food sources, such as fruits, vegetables, whole grain breads and cereals, and legumes (beans and peas) will ensure that not only will you get a good mix of fiber, but beneficial nutrients, too. Remember that brown rice and 100 percent whole wheat bread have more fiber than white rice or white bread. Also, eating the skins of your fruits and vegetables whenever possible can also help increase fiber intake. If you're a Columbia student and need advice or more information about incorporating fiber-rich foods into a balanced diet, you can make an appointment with a health care provider or a registered dietitian by contacting Medical Services (Morningside) or the Student Health Service (CUMC).
Hope this was helpful!
Dear Supplementally Confused,
It may depend on the type of dietary supplement. Supplements range from daily multi-vitamins and minerals to anabolic steroids. Certain supplements are recommended for various conditions. For example, calcium supplements are often encouraged to help prevent osteoporosis, and iron is recommended for those who are anemic. Pregnant women's increased nutritional needs may require that they supplement with vitamins and minerals. The performance enhancing supplements that are so widely advertised today (i.e., creatine, chromium picolinate, protein shakes, amino acids) are not needed by the average person.
The best way to get all of the nutrients your body needs is to eat a healthy diet. To do this, you should eat a variety of foods, have a good balance within the food groups (read Food Guidelines — How much is a serving? for details), eat enough calories (at least 1200), and make nutrient-dense choices, such as whole wheat bread and skim milk as opposed to white bread and whole milk.
Although vitamin and mineral supplements serve an important purpose for some people, you cannot depend on pills alone to provide your body with the nutrients it needs. Pills do not have phytochemicals, the non-nutrient compounds found in plant-derived foods that have biological activity in the body. Approximately 150 phytochemicals are found in foods along with the vitamins and minerals the body needs. Phytochemicals play a very important role in helping the body defend itself against cancer and cancer-causing agents, and probably many other things as well. An example of a known phytochemical is beta-carotene, a carotenoid. It is found in deeply pigmented fruits and vegetables, such as carrots, sweet potatoes, tomatoes, spinach, broccoli, cantaloupe, pumpkin, and apricots. Carotenoids act as antioxidants, reducing the risk of cancer. Read Antioxidants for more info.
So the best bet is to do what you were told as a child and, "eat your fruits and veggies!" Five servings a day is a great start. If you do supplement, be careful not to overdose. More of a "good" thing is not necessarily good for you. Besides being expensive, over-supplementing can be harmful to you. For more information, read What's the difference between vitamins and minerals? from the Go Ask Alice! Nutrition & Physical Activity archives.
How much did you bet? It's time for your co-worker to pay up!
The human body can survive a surprisingly long time on water alone, but it is nowhere near six months. When the body is deprived of new fuel (i.e., food), it breaks into its energy reserves to keep going. The body stores energy in the form of carbohydrates, fats, and proteins.
After one day without food, the body will have used up its carbohydrates, which are stored as glycogen in liver and muscle cells. After that, it's on to the fat reserves. Your average Joe/Jane, weight-wise, has enough fat reserves to live for four to six weeks without food. After that, the body begins to use its protein reserves (basically, the body itself). Body proteins are used up at a much faster rate than fat, and you could really only get another two to three weeks out of protein. At that point, however, you can't really call it living since so much irreparable damage has been done to the body, including the brain.
Bottom line: an average person could live for about eight weeks on water alone, give or take about a week for an over- or underweight person, respectively.