June 10th, 2009 by admin in Better Health Network
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Have you ever thought about how much protein you are supposed to get each day? The answer to that question is not as black and white as you may think.
The Recommended Dietary Allowance (RDA) for protein is set at 0.8 grams (g) per kilogram (kg) of body weight. In order to figure out your weight in kg, divide your weight in pounds by 2.2. So if you weigh 150 pounds (68.2 kg), you need about 55 grams of protein. You can also use 0.36 grams per pound of body weight if you don’t want to convert to kg.
The RDA is set at a level of what you need to prevent deficiency. But many researchers believe that we actually need more than that for reasons of muscle building and for optimal satiety (to keep us full).
Here are some other recommendations:
Pregnancy/lactation: 1.1 g per kg body weight (0r 0.5 grams per pound). You can use pre-pregnancy weight for the calculation. The point is you need significantly more protein when pregnant. Add 25 grams more per day if you are carrying multiples. This extra protein is especially important in the second half and third trimester. You can also use 0.55 grams per pound body weight to calculate.
Endurance athletes: 1.2-1.4 g per kg body weight (or 0.55-0.65 grams per pound). Endurance athletes often think of carbs, carbs, carbs, and they ignore protein. But you are using your muscles quite a bit and need extra protein to repair them. Endurance athletes would be runners, bikers, long distance swimming, etc.
Strength athletes: 1.6-1.7 g per kg body weight (or 0.73-0.77 grams per pound). Strength athletes are pushing their muscles to the extreme and need more protein to build and repair those muscles. But don’t skimp on carbs because your body will break down protein for energy if you don’t get enough carbs. Strength athletes are people who do a signficant amount of strength training and may lift very heavy weights.
An upper limit of protein has not really been established, but many researchers believe that the body cannot use much more than 1 gram of protein per pound body weight.
This post, How Much Protein Do You Really Need?, was originally published on
Healthine.com by Brian Westphal.
November 15th, 2008 by Dr. Val Jones in Expert Interviews
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It is estimated that 75% of our healthcare dollars are spent on chronic disease management, and that 80% of chronic diseases could be avoided with diet and lifestyle interventions. This means that the best way to decrease the size of our healthcare budget is to decrease the size of our collective waistlines. And that’s no small task.
Going back to basics – healthy eating and regular exercise – is such a simple message. But what is healthy eating exactly? Consumers are fairly exhausted by the complex messages they’ve heard about food and nutrition over the past couple of decades. One minute anti-oxidant foods are a miracle cure for everything from cancer to facial wrinkles, the next, it seems that they actually increase the risk of death. Diet advice ranging from low fat, low carb, to low sugar have all been promoted as the healthiest way to lose weight. But what does the evidence actually show? I decided to interview a series of experts to try to glean what I could about the state of nutrition knowledge. Today’s post is about protein – and I interviewed Nancy Rodriguez, PhD, a “protein scientist” to weigh in on this nutrient.
Dr. Val: We don’t talk about dietary protein needs that much, Nancy. Why is that?
Dr. Rodriguez: In the United States most people do get at least the minimum required amount of protein/day. The RDA (recommended daily allowance) of 0.8g/Kg of body weight is the amount you need to consume to avoid an outright protein deficiency. That’s about 3 ounces of chicken, fish, or meat/day – the size of a deck of cards. But the real benefits of protein include appetite suppression, and thermogenesis. Studies show that if people eat a little bit of protein with each meal, they’re less likely to become hungry between meals or consume as many calories overall. You also end up burning a few calories in the process of digesting protein.
Dr. Val: So what is the appropriate amount of protein intake?
Dr. Rodriguez: I have found that 1.2-1.5g/Kg may be optimal for hunger management. That means we should try to get a little bit of protein with each meal. Weight maintenance and loss is much easier to achieve if you don’t feel hungry all the time. Protein can really help with that.
Dr. Val: Is it possible to eat too much protein? Can it damage the kidneys in excess?
Dr. Rodriguez: I’ve conducted a few studies with participants eating 3g/kg of protein. That’s really hard to do. For example, you have to eat eggs and bacon for breakfast, 2 chicken breasts and veggies for lunch, and a 10oz steak for dinner. This is clearly in excess of what we need, though it’s hard to say if that level of protein is harmful. If someone has kidney disease, then obviously it would be a really bad idea to tax the kidneys with removing so many protein break down products. But people with normal kidney function didn’t seem to have a problem clearing the protein. Protein isn’t stored. When you consume more of it than your body needs, it is simply broken down and removed via the urine.
I personally don’t believe that excess protein causes kidney disease, but it can be a problem for those who have kidney disease. We would have to do some very long term studies of people eating very high protein diets for decades to find out if they end up with a higher risk of kidney disease. We just don’t know yet. But our kidneys have a tremendous reserve capacity to filter the blood. We can easily live with just one kidney – so it’s possible that healthy kidneys can handle high protein diets without injury. One thing that I certainly recommend – if you eat a lot of protein, you should drink a lot of water to help to flush out the break down products.
Dr. Val: Is it true that whey protein may help to reduce high blood pressure?
Dr. Rodriguez: Milk proteins are very interesting in that they contain a broad array of bioactive substances. There is increasing evidence that lactokinins can reduce blood pressure, but we just don’t understand the exact mechanism yet. We do know that people who eat more dairy products (included in the DASH diet plan) can lower their systolic blood pressure by an average of 10 mmHg.
Whey protein is also a natural appetite suppressant, so it can be helpful part of a weight loss strategy. Dairy sources of protein are an important part of a healthy diet.
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I caught up with Nancy at the Dairy Science Forum on November 13th, 2008 in Washington, DC.
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Nancy Rodriguez
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Nancy Rodriguez, PhD, RD, CSSD, FACSM, is a professor of Nutritional Sciences in the College of Agriculture and Natural Resources (CANR) at the University of Connecticut, with joint appointments in the Departments of Kinesiology and Allied Health Sciences. She is director of Sports Nutrition in the Department of Sports Medicine in the Division of Athletics.
November 1st, 2008 by Dr. Val Jones in Expert Interviews
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Tanya Altmann, MD
It’s been a little while since I had a “blonde moment” during an expert interview, but this one was pretty funny. I was in the middle of a podcast with Dr. Tanya Altmann, media personality and spokesperson for the American Academy of Pediatrics, about vitamin D – when I thought I heard her say that there were now special formulas of vitamin D for incense.
I knew that Dr. Altmann practiced medicine in Southern California, so I wasn’t terribly surprised about this new method of vitamin delivery. However, I hadn’t heard about vitamin D inhalation previously, so I asked her to explain how this new incense formula worked.
She paused to gather her thoughts and then corrected me: “No, I was saying that there’s a new formula for INFANTS…”
Oh. My bad.
So here’s the rest of our delightful interview. You may want to listen to the podcast, though I did edit out the awkward “incense” section so as not to start a new cult. One doesn’t want to give others too many ideas on the Internet! I hope that Dr. Tanya won’t think less of me for that misunderstanding.
Dr. Val: What is vitamin D, and why do we need it?
Dr. Tanya: Vitamin D is an essential nutrient for your entire body. Although it’s called a vitamin it actually functions as more of a hormone, playing an important role in the immune system. Vitamin D can help to protect people against illness, diabetes, and even cancer, though its role in helping to build strong bones (and protect infants from rickets) is probably its best known attribute.
Dr. Val: Tell me about the new AAP guidelines for infants, children and adolescents. Why did they change?
Dr. Tanya: Based on data collected in several recent research studies, the American Academy of Pediatrics issued new guidelines last month which essentially doubled the recommended daily amount of vitamin D (from 200 to 400 IUs) for infants, children, and adolescents. Historically people were able to get sufficient amounts of vitamin D through sun exposure (the body can create vitamin D when the skin is exposed to sunlight), but now that we need to protect kids from sun’s harmful rays due to future skin cancer risk, vitamin D levels have dropped significantly. Sunscreen, of course, blocks the sun from stimulating the creation of vitamin D in the skin. Read more »