Nutrition & Physical Activity

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All about Hoodia

Dear Readers,

Hoodia has been touted as a succulent that has remarkable appetite-suppressing qualities, but thus far, those claims don't hold water. The Hoodia craze has been fueled by the pharmaceutical companies in the U.S. and South Africa who claim that the San, a tribe in Africa, consume the Hoodia to stave off hunger and/or thirst during their long treks through the Kalahari Desert.

Researchers have isolated a set of chemicals, called P57, thought to be the cause of the appetite-suppressing qualitites of Hoodia. Researchers injected the P57 into rats. It appeared to suppress the rats'  appetites, without causing other effects. A series of follow-up studies have indicated that the chemical acts on the appetite-regulation center of the brain, which is located in the hypothalamus. Few studies on Hoodia's effect on humans, however, have been conducted. As a result,  many health care providers are hesitant to support the use of Hoodia as either effective or safe.

The drug company Pfizer worked for years to develop Hoodia as an obesity drug but gave up after they could not create an acceptable synthetic version. What remains unclear is whether or not the supplement could actually help a person shed pounds, whether or not it could do so safely, what the long-term effects of taking it might be, and what dose would be needed for it to work.

Also up for debate is whether or not the San people actually consume the plant as an appetite suppressant. Many contend that the cactus is consumed for its water content. And even if it did work as an appetite suppressant for the San, the conditions of life in the U.S. are remarkably different (i.e., the San are more physically active, people in the U.S. consume a very different diet, and have more access to food than the San).

The final concern with Hoodia has to do with the lack of diet industry regulations in the U.S. As with many supplements, the amounts of Hoodia in each type can vary greatly. Some companies even sell Hoodia supplements that contain no Hoodia!  Further, no research is available to support what dose of Hoodia is needed to produce the desired effects safely.

Overall, the research indicates that Hoodia is safe; however, its effects  may be limited. Hoodia may be nothing more than a placebo. Check out I need an effective, short-term weight loss and toning plan for more well–researched methods of weight loss.

Take care,

Alice

Avocados — which variety is the healthiest?

Dear Reader,

No matter the color, shape, or size, avocados are delicious — and nutritious! There are a wide variety of avocados on the market, each with a unique flavor, texture, and nutritional value. Thanks to alternating shipment seasons, people across the United States have access to avocados all year round. California and Florida produce the vast majority of avocados in the United States.

California avocados largely consist of the Hass variety, which are the most widely available type on the market. They have thick, leathery skin that turns dark green-to-black as the fruit ripens. California ships avocados throughout the United States, even all the way to Florida and other states on the East Coast. These medium-sized fruits weigh approximately 4.8 ounces (136 grams), and contain:  

  • Approximately 227 calories
  • 2.9 grams of saturated fat
  • 13.3 grams of monounsaturated fat
  • 2.5 grams of polyunsaturated fat

Florida avocados are all members of the green-skinned avocado family. These have less fat, but more moisture than the Hass, and thus are not as sweet and nutty tasting. As they ripen, green-skinned avocados retain their light-green skin. Green avocados tend to bruise more easily during shipment because of their thinner skin, restricting shipments from Florida to primarily Eastern U.S. markets. These avocados tend to be larger in size, and typically weigh a hefty 10.7 ounces (304 grams). One green-skinned avocado contains:

  • 6 grams of saturated fat
  • 16.8 grams of monounsaturated fat
  • 5.1 grams of polyunsaturated fat

No matter their hue, eating both black and green avocados provides multiple health benefits, including:

  • Acting as a "nutrient booster" by enabling the body to absorb more fat-soluble nutrients in foods that are eaten with the fruit, such as alpha- and beta-carotene.
  • Providing more than 25 essential nutrients, including fiber, potassium, vitamin E, B-vitamins, and folic acid.
  • Providing consumers with a healthy source of fat. The avocado is virtually the only fruit that has monounsaturated fat (a.k.a. good fat).
  • Providing a good source of fiber.

Adding heart-healthy unsaturated fats to your diet, available in avocados, nuts, and olive oil, may help you make the most of your fruits and veggies and eat a more balanced diet. One delicious way to eat avocados is using avocado spread in place of high-fat spreads, such as butter and mayonnaise. For more information, you can check out Avocados are fatty — are they healthy?.

See you…avocado go now!

Alice

Can't stay healthy for qualifying exams

Dear Dizzy and stressed,

Putting your health first during exam time can be a challenge, but if you want to score well, take care of yourself now! If you are experiencing such extreme dizziness and discomfort it is of utmost importance to seek out medical care immediately. Now, let's tackle some of the related issues you brought forward in your question.

Eating disorders, such as anorexia, can take enormous tolls on your health, including fatigue, dizziness, and/or fainting, irregular heart rhythms, low blood pressure, and dehydration. While you may have found a healthier place regarding anorexia, it is likely that your symptoms are related to your current eating patterns. These symptoms can have major negative effects on your body, and it is recommended that you take action as soon as possible. You may want to call The National Eating Disorders Association eating disorders information and referrals line at 1.800.931.2237. More information can also be found in Eating disorder resources on the web.

In your situation, it may be highly beneficial to learn how to manage stress in a constructive way. Fortunately, there are many things you can do to decrease your stress and up your wellbeing. Some people exercise, meditate, breathe deeply, pursue a hobby, and/or seek support from others. Don't forget about your ZZZ's, too! Chronic sleep deprivation (going for extended periods of time with less sleep than your body needs) can cause a variety of physical and psychological problems. You may want to check out The downsides of sleep deprivation for more on this topic.

Finally, you may want to address your smoking habits and soda intake. Excessive soda consumption (such as consuming at least 2 liters of diet coke per day) can have significant consequences on your health. Soft drinks are acidic, which can wear down tooth enamel and cause tooth decay. Too much caffeine can cause anxiety and sleep loss. For quitting colas, you may want to check out Getting off colas. Cutting out the chain smoking can improve your respiratory and heart health as well. 

It may be a long and arduous road to addressing your health concerns, but it will sure be worth it (for your overall well-being and your academics)!

Alice

I'm worried my boyfriend has bulimia

Dear Reader,

It can be tricky to check in with a loved one about the concern that they may have an eating disorder. You may be afraid that you'll say something that might shut them down or hurt their feelings. You may be afraid that you're mistaken. This worry may be especially great for you since eating disorders are more prevalent in women (though eating disorders are more common among men than many people realize). Don't let these worries stop you from having an honest conversation about what you have observed and what your concerns are.

First, how might you recognize if a loved one has an eating disorder? There are a few different types of eating disorders, but you need not worry about making an "exact diagnosis." The following may be warning signs of bulimia, but a loved one need not exhibit all these signs in order to have it.

  • Frequent complaining or worrying about being overweight.
  • Use of "purging" tactics for weight loss, including excessive exercise, herbal weight loss supplements, weight loss medications, laxatives, or forced vomiting after eating.
  • Not wanting to eat in front of other people.
  • Eating large quantities of food in one sitting.

Warning signs of Anorexia can include:

  • Significant weight loss.
  • Enjoyment of cooking and preparing meals for others without eating much.
  • Significantly distorted body image — sees self as overweight, when he or she is likely significantly underweight.

Some people with eating disorders recognize that they have one, but are afraid to reach out for help. They may be afraid of being judged and/or losing loved ones if they open up about their eating disorder. Others may be in denial about having an eating disorder, while others may have such a low self-esteem that they feel, either consciously or unconsciously, that they do not deserve help. If you are afraid to check in with him about the possibility that he has an eating disorder, it may be helpful to know that eating disorders do not go away on their own and they can have severe health consequences. So the sooner he seeks help, the better his chances of recovery and the less damage that will be done.

But how to bring this up? There are a few good guidelines to cover that will help you convey a nonjudgmental attitude and also help ensure you are respecting your boyfriend's privacy:

  • Make the basis of the conversation about your worry. Try to remain positive while also explaining that you care about him and because of this, you are worried about his health and his emotional state.
  • Avoid comments about his appearance. Some people with eating disorders will not be affected, while others will be extremely affected by hearing your assessment of their weight (e.g. they may be flattered or they may be horrified. Either way, you may inadvertently reinforce their restricted eating or purging).
  • Do not demand that he eat or change his behavior.
  • Avoid placing blame or giving advice.
  • Watch out for accidental "fat phobic" remarks that you might make inadvertently (in other words, avoid making disparaging remarks about weight or overweight people). Avoid making remarks even about your own body weight.

Aside from offering you nonjudgmental support, the most important thing you can do for a person with an eating disorder is to encourage him or her to get treatment. The longer an eating disorder remains undiagnosed and untreated, the harder it is on the body and the more difficult to overcome, so urge your boyfriend to see a therapist or his health care provider right away. If your boyfriend is a Columbia student, he can make an appointment with Counseling and Psychotherapy Services (CPS) or with his primary care provider through Open Communicator.

It may also be worth checking out the following resources:

Recovering from an eating disorder usually takes time. Kudos to you for your patience and your willingness to support someone struggling with an eating disorder. This may at times be difficult for you, too, so make sure you are getting support, as well, whether it be through friends, family, and/or therapy.

Take care,

Alice

Raisin bran confusion — is it a good source of iron?

Dear Reader,

Props to you for wanting to donate blood! Alas, isn't it iron(ic) that one of the foods with higher iron content also may contain an iron absorption inhibitor? It's one thing to worry about getting enough iron through your food sources, but a whole other thing to worry about whether that iron is actually being absorbed. Boosting your hemoglobin by upping your iron intake shouldn't be too tricky, but know that there are a number of possible causes for low hemoglobin — being low on iron is only one cause (more on that later).  

Let's discuss the raisin bran question first. Phytic acid is often found in foods that contain whole grains, including some types of raisin bran. In large enough quantities, phytic acid can inhibit your body's iron absorption. This is annoying since these foods may also be high in iron. In addition to iron absorption inhibitors, there are also substances that aid in iron absorption. The primary is vitamin C, which is often also found in raisin bran. Your best bet is to check food labels so you know when you are consuming foods that contain phytic acid (and also whether it contains a substance such as vitamin C, which will help you absorb iron). If food products contain iron and phytic acid, chances are you'll still likely get at least some iron benefit from them (especially if that food contains vitamin C, too); however, it's wise to have additional sources or iron other than raisin bran. Another iron absorption inhibitor is tannic acid, which is often found in red wine, coffee, some teas, chocolate, and some sodas.

So what does all this mean? Diversified food sources of iron will be your best bet in ensuring that you meet your recommended daily allowance, but there's no harm in making raisin bran one of those sources. Check out the Q&A's below for more information on iron, how much you need, and getting enough of it through your diet.

Now, are you sure low iron is the cause of your low hemoglobin? There are several other possible causes. Cirrhosis (scarring) of the liver is one cause. Some common causes of cirrhosis include alcohol abuse, hepatitis B or C, cystic fibrosis, and some parasites caused by chronic liver damage. These conditions, as well as the cirrhosis itself, would likely be accompanied by additional symptoms, such as fatigue, nausea, weight loss, and/or easy bruising.

Other causes can include certain cancers of the blood (e.g. leukemia, multiple Myeloma) or of the lymphatic system (e.g. Hodgkin's and non-Hodgkin's lymphoma), enlarged spleen (splenomeglamy), or vasculitis (inflammation of blood vessels caused by an autoimmune response of various origins). Though anemia and iron deficiency are common causes of low hemoglobin, it may be worth a trip to your health care provider to rule out these other causes.

Happy hemoglobin boosting!

Alice

Relaxation drinks

Dear A Sip of Calm,

Can we actually find relaxation in a can? Seems like it could be a great idea, unfortunately, at this point in time, it's just too good to be true. Just like herbal supplements, the FDA does not require companies manufacturing the "relaxation beverages" to prove their claims or standardize their ingredients. As such, there is no conclusive scientific evidence that any of these products are safe and effective. What little research has been done has shown that many compounds in these drinks, such as 5-HTP and melatonin, degrade in water. Other ingredients  such as GABA, cannot cross the blood-brain barrier so are completely ineffective. One study even tested five popular brands and found that many of the ingredients listed were barely even present in the drinks themselves!

Two popular ingredients in relaxation beverages that have been studied are valerian and kava and the news is not good. Valerian can cause dependency if taken regularly while kava has been shown to cause liver damage. These types of ingredients can also interact with medications such as Allegra or benzodiazepines (Xanax, Valium, Atvian, etc.) or even with Tylenol and cause serious health problems.

What's your best bet for relaxation? For starters, maintaining a proper diet, exercising, and trying to keep a regular sleep schedule can contribute to feelings of relaxation. You may also want to try meditation and/or yoga.  

In the end, it seems as if nothing beats a glass of warm milk or hot (decaf) tea to unwind in the evening.

Alice
Assigned researcher

Does exercising on an empty stomach maximize fat burning?

Dear Reader,

First things first: Great job staying active! Now, on to your very interesting (and slightly complicated) question. As you have already noticed, there are many schools of thought on the issue of maximizing fat loss. Do you exercise on an empty stomach or do you make sure and eat a little something before your morning run? Sifting through all this information can indeed be confusing. Let’s get to the bottom of the issue.

The latest research seems to indicate the following: If you will be exercising longer than 30 minutes, eat a light snack in the morning before you run. It’s a good idea if that snack contains some carbohydrates and some protein (i.e. a banana with peanut butter). This allows your body to use the carbohydrates to help burn fat in your body and the protein will keep you going past that 30 minute mark. However, if your aerobic workouts are less than 30 minutes, exercising on an empty stomach may indeed be the most beneficial for fat-burning.

Carbohydrates are the easiest for your body to burn — they require the least amount of oxygen. Fat, the body’s long–term energy storage mechanism, takes more oxygen. If no carbohydrate is present (i.e. an empty stomach), your body will burn fat for energy. But your body will also start burning protein. Herein lies the catch to performing aerobic exercise on an empty stomach: You may experience some muscle loss, especially if your work out is 30 minutes or longer. Here are a few more things to consider:

  • Not eating before a workout may cause you to fatigue faster, thereby shortening or lowering the intensity of your workout.
  • Exercising on an empty stomach can decrease blood sugar levels, which may make you hungrier and more prone to overeat at your next meal.

Lastly, individual bodies with different metabolisms do this sugar-protein-fat dance slightly differently. For example, certain types of health conditions, such as diabetes and low blood pressure, necessitate eating before exercising, as a cardio workout on an empty stomach could cause other health problems. Medical conditions aside, some people are more prone to muscle loss than others, and some will burn fat more quickly or easily than others. Additionally, the altitude at which you work out makes a difference. People exercising at higher altitudes have less oxygen at their disposal, so running at a slower pace, which will lower your heart rate, will help you burn more fat. Many trainers say that to maximize fat burning, you should do your cardio workout at a level that allows you just enough breath to hold a conversation.

Columbia students interested in more physical activity information can by sign up for Columbia's CU Move motivational emails. You can also visit the CU Move webpage for other physical activity related information. Best of luck to you on your morning workouts!

Alice

Overcooked pasta and beans — Still nutritious?

Dear Long Cooker,

Whether you’re an avid chef or a microwave maven, it is important to know that overcooking can deplete the amount of vitamins and minerals in foods. If you are cooking your pasta and beans for as long as you say, you are most likely losing some of their nutritional value. Overcooking destroys bonds between molecules, significantly depleting the nutritional value. For example, overcooking can destroy amino acids and many of the B vitamins, such as Vitamins B-1 and B-5. These vitamins are important for metabolism and energy production.

Generally, shorter cooking time retains more nutrition in a food. Here are a few basic cooking guidelines for your pasta and beans:

Beans, peas, and lentils (members of the legume family) are low in fat and high in fiber, making them a healthy part of your diet. Cooking your beans properly can make them a nutritious and delicious addition to a meal. Dried beans should be soaked overnight in fresh water. They are then cooked for 1-3 hours, depending on the variety of bean. This is standard preparation, and beans cooked in this manner are full of nutrients.

Pasta is a complex carbohydrate, with more fiber and a lower glycemic index than simple sugars. Overcooking pasta can strip it of its fiber content. Most pasta only needs to be boiled between 5 and 15 minutes, depending on the cut of the noodle. Overcooking pasta will only add to the loss of vitamins (especially water-soluble B vitamins) and minerals that occurs when you cook it. Another tip: try not to rinse cooked grains and pasta, as this causes further loss of nutrients.

The style of cooking plays an important role in the overall nutrition of food as well. Whether fresh, steamed, baked, grilled, boiled, or fried, how food is prepared can modify the nutritional content. For instance, boiling leeches more nutrients out of vegetables and beans than baking, as many of the vitamins in vegetables are water-soluble. Steaming and microwaving your food can help maintain the most nutrients.

Bon appétit!

Alice

All torn up over stretching

Dear All Torn Up,

Don't get all strung out! Contrary to popular belief, inadequate stretching is not the cause of all injuries. However, sticking with a stretching routine over an extended period of time can lead to increased flexibility and range of motion. The correct type of stretching depends on what physical activity you are involved in, as well as how much weightlifting you do. Getting muscle-specific will help target the muscles and joints that you exercise most.

There are three main types of stretching techniques: static stretching (holding a stretch for an extended period of time), dynamic or ballistic stretching (moving your muscles towards their maximum range of motion in a bouncing manner), and proprioceptive neuromuscular facilitation (alternating passive stretching and isometric contractions). Static stretching is the most commonly used form of stretching, and the other two are generally done under the supervision of athletic trainers or physical therapists due to the risk of injury.

For those wishing to stretch before exercise, it's best to stretch following a mild warm-up, such as aerobics, walking, light jogging, or any activity that slowly raises heart rate. A warm-up increases body temperature and warms the body's muscles and tendons, making them less likely to tear or pull easily. Stretching after exercise relaxes muscles and may prevent tightness. While it is not proven that stretching before and after exercise reduces soreness, some people feel better after stretching. Some people like to stretch during their cool-down routine.

Remember, it's recommended that you match the type of stretching that you do with the muscles that you use during your exercise routine. Here are some general guidelines for healthy stretching:

  • Stretch the muscle groups that you use most on your exercise routine.
  • Apply at least four to five 60-second stretches to the targeted muscle groups, making sure you're stretching both sides of the body equally.
  • Only stretch until you feel the stretch, not pain.

One thing to keep in mind is that studies are inconclusive as to whether or not stretching helps decrease sports injuries. In fact, research has identified other factors that could be more closely related to sports injuries. These include a history of chronic or recent injury, having a higher body mass index (BMI), and switching pre-participation stretching routines (that is, those who normally stretch before an activity suddenly stopping). Here are a few suggestions to help prevent sports injuries:

  • Maintain strength in the muscles surrounding the joint.
  • Cross train to mix up your workouts and to prevent repetitive motion injuries.
  • Include a warm up in your routine, such as dribbling for soccer, skating for hockey, and a few laps for swimming.
  • Never skip your warm-up or cool down.
  • Don't drastically change your warm-up routine. Sudden changes to your warm-up can also increase your risk for injury.
  • Use proper technique and form to minimize your risk of injury.
  • Keep your cardiovascular health up — a stronger heart allows you to keep up your strength and avoid risky errors that could lead to injury.
  • Use proper protective equipment, such as knee and shoulder pads.

All in all, there are many factors that go into injury prevention. Your coach, physical therapist, or health care provider may be able to give you a few pointers on keeping your body healthy during exercise.

Learning more about injury prevention is the ultimate home run. Batter up!

Alice

For more information or to make an appointment, check out these recommended resources:

Medical Services (Morningside)

Student Health Services (CUMC)


Androstenedione — is it safe?

Dear Reader,

While it appears that androstenedione has helped some people (a few prominent athletes included) increase their muscle mass and recover more quickly from injury, there is no scientific research supporting these results. In order to help you decide whether such nutritional supplements are right for you, let’s first take a look at androstenedione.

Androstenedione is a direct precursor hormone to testosterone and other hormones including one type of estrogen. It is converted from cholesterol, as are all other steroid hormones. Specific enzymes and hormones, among other things, must be present and ready to work for these conversions to take place. For instance, luteinizing hormone, produced and released by the pituitary gland, plays a pivotal role in converting androstenedione to testosterone. Simply introducing extra androstenedione to your system does not automatically indicate that all of the necessary players will be there to produce testosterone or improve the productivity of your workout.

About sixty years ago, when androstenedione was first synthesized, it was shown to have both androgenic (male hormone-like) and anabolic steroid-like properties. The anabolic effects were considerably less than those of testosterone. Subsequent research found that testosterone levels rose after inhalation of androstenedione, but remained elevated for only a couple of hours, with peak levels lasting a few short minutes.

Beyond these cursory early studies, rigorous studies have come to two broad conclusions about androstenedione. First, despite increasing testosterone levels for those with low baseline testosterone levels such as women and older men, androstenedione has not been shown to increase the testosterone levels of young men or to improve the effectiveness of their exercise regiments aimed at building muscle.

What side effects can you expect from androstenedione? No one knows for sure. Androstenedione  falls under the category of steroid hormones, which are known  to have androgenic and anabolic properties. Therefore, androstenedione may produce side effects similar to those of testosterone-based anabolic steroids. The most dangerous of these side effects is the increased risk for cardiovascular disease, certain cancers, depression, psychoses, and even extreme aggression. There are also gender-specific effects. For men, these include shrinking testes, increased hair loss, enlarged breasts, and possible sterility. Women may experience side effects such as shrinking breasts and uterus, enlarged clitoris, irregular menstruation, increased facial and body hair growth, and a deepening voice. In fact, due to many  potential negative health hazards, the Food and Drug Administration (FDA) has prohibited the sale of over-the-counter androstenedione and similar steroid-like dietary substances.

Is it safe? Safety can be difficult to determine when you don't really know what you're dealing with. Is it worth the risk? That's for you to decide. Before you begin taking any dietary supplements you may want to speak with your healthcare provider. S/he can answer your questions and give you more detailed information. Columbia students might want to consider making an appointment at Medical Services by calling x4-2284 or online using Open Communicator. Students on the Medical Center campus can contact the Student Health Service.

Alice

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