Recipe Review: Curried Yellow Split Pea Soup with Spinach

Submitted By Amy Sercel MS RD CD

Edited By Marcia Bristow MS RDN CSSD CD

Prep Time: 20 minutes

Cooking Time: 45 minutes

Ingredients:

2 tsp vegetable oil

1 cup onion, chopped

1 clove garlic, chopped

1 ½ tsp fresh ginger, finely chopped

½ tsp ground cumin

½ tsp curry powder

¼ tsp turmeric

¼ tsp ground coriander

¼ tsp cayenne

2 cups dried split yellow peas

1 ½ cups fresh spinach, shredded

½ tsp salt

Instructions:

1.     In a large soup pot, heat oil over medium heat.  Add onion and garlic and cook until soft, 3-5 minutes.

2.     Add ginger, cumin, curry powder, turmeric, coriander, and cayenne.  Cook, stirring, 1 minute to toast the spices. 

3.     Add the split peas and 8 cups of water.  Bring to a boil over high heat.  Reduce heat to medium-low, cover, and simmer until split peas are soft, about 45 minutes.

4.     Add spinach and salt.  Cook until spinach wilts, about 1-2 minutes.  Soup will thicken upon standing.  Add additional water to thin as desired.

Yield: 8 servings

Nutrient Facts:

203 calories, 12 g protein, 31 g carbohydrate, 4 g fat, 12 g fiber

37 mg calcium, 581 mg potassium, 156 mg sodium, 2 mg iron, 59 mg magnesium

39 mcg vitamin A, 5 mg vitamin C, 1 mg vitamin E, 45 mg vitamin K, 106 mcg folate

This recipe is quick, easy, and excellent for a cold winter night!  It is flavorful and satisfying but low in calories and fat, making it a great option if you are looking to keep your energy intake low.  My family found it delicious – everyone asked me for a copy of the recipe!  I doubled the amount each spice, but you could definitely use less if you prefer a milder meal.  You could also consider personalizing the soup by adding some cauliflower, bell peppers, mushrooms, winter squash, or kale about halfway through the step of simmering the split peas.  I recommend doing this if you’re thinking of making this a one-pot dinner, since the original recipe doesn’t call for many vegetables.

You don’t have to plan very far ahead to make this recipe.  Depending on how stocked your spice cabinet is, you probably have almost all of the ingredients in your pantry already, and you’ll only have to chop the onion, garlic, ginger, and spinach.  I would suggest chopping the garlic, onion, and ginger before you start cooking so you can sauté everything immediately without worrying that it will burn while you are chopping the next ingredient.  Once you add water the soup needs to simmer for about 45 minutes, which will allow you plenty of time to chop the spinach, prepare a side dish or just relax before eating. 

I served this dish with brown rice and steamed broccoli to give the meal some extra color and texture.  My family loved the way the brown rice complemented the soup.  The rice also boosts the meal’s protein content a little, providing the essential amino acids that are missing from the split peas to create a complete protein.

If you aren’t used to cooking with yellow split peas, you can find them in the same aisle as canned beans in your grocery store.  Yellow split peas are a relatively inexpensive and nutritious source of protein.  They’re high in folate, a vitamin that helps keep your immune system strong and your heart healthy.  They’re also high in fructans, a type of fiber that promotes the growth of healthy gut bacteria.  Overall, this is a nourishing meal that is sure to become a go-to on those busy days when you aren’t sure what to have for dinner.

Recipe Source: http://www.food.com/recipe/curried-yellow-split-pea-soup-with-spinach-206923

Exercise to Lose Weight? Maybe Not

Submitted By: Amy Sercel MS RD CD

Edited By: Marcia Bristow MS RDN CSSD CD

Often when people have a goal of losing some weight, their first strategy will be to work out more often.  It’s possible that you’ve even tried this in the past.  If so, you might have noticed that exercising more does not always result in the weight loss you want, or may lead to a slight weight gain.¹

The truth is that exercise alone isn’t enough to achieve significant weight loss.  In order to lose weight you need to burn more calories than you eat, which creates something called an energy deficit.  As a general rule, you need a deficit of 500-1,000 calories each day to achieve a healthy weight loss of 1-2 pounds per week.  Unfortunately, the number of calories you will burn through exercise is affected by your age, gender, ethnic background, body mass index, and genetics, so it’s hard to estimate how much exercise you need in order to create enough of an energy deficit to lose weight.²

It’s common to overestimate the number of calories you burn during exercise and underestimate the calories you eat.  Some foods are surprisingly high in calories, and you might not burn as many calories through exercise as you think.  If you weigh 150 pounds, here are some activities you would need to do to burn off different foods:^3,4

• Walk briskly for 30 minutes to burn off a 12-oz beer with 150 calories
• Swim for 1 hour to burn off a bagel and cream cheese with 450 calories
• Run 4 miles to burn off a 16-ounce mocha latte with 400 calories
• Lift weights for 1 hour to burn off 2 tablespoons of Nutella with 200 calories
• Row for 45 minutes to burn off a medium serving of French fries with 365 calories

In addition to taking a longer than you realize to burn off the calories you eat, it’s also possible that your body will make up for the calories you burn through exercise by slowing your metabolism or producing hormones that make you feel more hungry.  In one study, 35 people exercised long enough to burn 500 calories per day for five days each week.  While in theory everyone in the study should have lost weight, half of the participants either didn’t lose weight or gained weight.  These participants reported feeling hungrier than usual and ended up eating an average of 270 calories per day more than they did before starting the program.⁵ Other studies suggest that the number of calories you will burn through exercise levels off as you get more active because your metabolism slows down in response to your increased activity level.^6,7 

Although exercising alone might not be the most effective way to lose weight, it can certainly contribute to the energy deficit needed for weight loss, and there are many other reasons to be active.  Regular physical activity can help prevent further weight gain, and can also reduce your risk of heart disease, diabetes, and some cancers.  It will also help you maintain your balance and muscle mass as you get older and can help keep your mind sharp.⁸ If you are looking to lose weight, create an energy deficit by filling up on low-calorie fruits and vegetables and choosing smaller portions.  Make an appointment with a Registered Dietitian to learn how many calories you should eat every day, develop strategies to make dietary changes that will work for you and set realistic physical activity goals.  This way, you will form healthy habits that will help you lose weight and maintain your weight loss.

References:

1. Liebman B. You should exercise to lose weight, right? NutritionAction.com. November 2016. http://www.nutritionaction.com/daily/exercise-for-health/exercise-to-lose-weight/?mqsc=E3859437&utm_source=WhatCountsEmail&utm_medium=Nutrition_Action_Daily_TipsNutrition%20Action%20Daily&utm_campaign=2016.11.25%20Exercise%20for%20Health. Accessed November 25, 2016.

2. Thomas DM, Kyle TK, Stanford FC. The gap between expectations and reality of exercise-induced weight loss is associated with discouragement. Prev Med. 2015;81:357-360. doi:10.1016/j.ypmed.2015.10.001.

3. Publications HH. Calories burned in 30 minutes for people of three different weights. Harvard Health. http://www.health.harvard.edu/diet-and-weight-loss/calories-burned-in-30-minutes-of-leisure-and-routine-activities. Accessed December 13, 2016.

4. Food Nutrition Chart, Food Calorie Chart, Whats Cooking America. https://whatscookingamerica.net/NutritionalChart.htm. Accessed December 13, 2016.

5. King NA, Hopkins M, Caudwell P, Stubbs RJ, Blundell JE. Individual variability following 12 weeks of supervised exercise: identification and characterization of compensation for exercise-induced weight loss. Int J Obes. 2007;32(1):177-184. doi:10.1038/sj.ijo.0803712.

6. Pontzer H, Durazo-Arvizu R, Dugas LR, et al. Constrained Total Energy Expenditure and Metabolic Adaptation to Physical Activity in Adult Humans. Curr Biol. 2016;26(3):410-417. doi:10.1016/j.cub.2015.12.046.

7. Byrne NM, Wood RE, Schutz Y, Hills AP. Does metabolic compensation explain the majority of less-than-expected weight loss in obese adults during a short-term severe diet and exercise intervention? Int J Obes. 2012;36(11):1472-1478. doi:10.1038/ijo.2012.109.

8. Physical Activity for Everyone: Guidelines: Adults | DNPAO | CDC. http://www.cdc.gov/physicalactivity/everyone/guidelines/adults.html. Accessed June 14, 2015.

Recipe Review: Butternut Squash White Bean Stew

Submitted By Amy Sercel MS RD CD

Edited By Marcia Bristow MS RDN CSSD CD

Prep time: 30 minutes

Cooking time: 35 minutes

Ingredients:

2 T olive oil

1 c slivered onion

¾ c sliced celery

3 c mushrooms, halved

4 c butternut squash, peeled and cubed

1 14-ounce can diced tomatoes

1 clove garlic, pressed

2 c water

2 T tomato paste

¾ tsp dried rosemary

½ tsp coarse salt

1 pinch black pepper

2 15-oz cans Great Northern beans, rinsed and drained

Chopped fresh parsley to garnish

Instructions:

1.     Heat oil in a large pot over medium-high heat.  Add onion, celery, and mushrooms.  Cook until vegetables start to brown, about 8 minutes.

2.     Stir in squash, tomatoes, garlic, water, tomato paste, rosemary, salt, and pepper and mix well.  Cover and bring to a simmer.  Reduce heat and simmer until squash is tender, about 25 minutes.

3.     Uncover, stir in beans and simmer until stew consistency, about 10 minutes.  Sprinkle with parsley, if desired.

Yield: 8 servings (1 ½ cups each)

Nutrient Facts:

247 calories; 14 g protein; 42 g carbohydrate; 4 g fat; 11 g fiber

163 mg calcium; 1245 mg potassium; 338 mg sodium; 5 mg iron; 108 mg magnesium

388 mg vitamin A; 25 mg vitamin C; 3 mg vitamin E; 13 mcg vitamin K; 129 mcg folate

My family thought this stew was delicious – the flavors blended together and complemented each other nicely.  As an added bonus, you might already have some of the ingredients in your pantry, and can stock up on the canned items to keep on hand for those busy nights when you aren’t sure what to make for dinner.

While you will spend about 30 minutes chopping the vegetables, you will have plenty of time to clean up the kitchen, prepare side dishes, or just relax in the 35 minutes it will take for the stew to simmer.  The most time-consuming part was peeling and cutting the butternut squash.  If you want, you can avoid this step by using pre-cut butternut squash from the produce section of your grocery store.

One of the best things about this dish is the fact that you can easily customize it to your tastes.  I left out the celery because of a food allergy and used additional mushrooms instead.  I also used tomatoes canned with basil, which gave the stew some extra flavor, and might consider adding a few tablespoons of fresh basil next time.  If you like spicy dishes, you could add some paprika or a chopped jalapeño pepper for an extra kick.  You could also sprinkle a little cheese on top for a savory touch.

This recipe is so satisfying and flavorful that you might not notice it’s both gluten-free and vegan.  The high fiber content in the squash, mushrooms, and beans will keep you full for a long time after eating and could help reduce your cholesterol levels.  Great Northern beans contain a lot of iron, which you will absorb more easily because of the vitamin C in the butternut squash.  The soup also contains about 25% of your daily need for potassium, an electrolyte that most people don’t get enough of.  Having adequate potassium in your diet can help keep your heart healthy and reduce your blood pressure. 

I ate this with steamed broccoli and garlic bread, but it could also pair well with a green salad, baked chicken, or a sandwich.  No matter how you serve it, this stew is sure to please even the toughest critic!

Recipe Source: http://relish.com/recipes/butternut-squash-white-bean-stew/

The Great American Protein Switch

 

Submitted by Megan Morris

Edited by Marcia Bristow MS RDN CSSD CD

Chicken or beef? These days, Americans are choosing chicken more and more often.¹ From 2014 to 2015 beef consumption fell about 0.3 pounds per person per year while chicken consumption rose about 5.8 pounds.¹ What does this “protein switch” mean for the health of Americans?

Chicken and other poultry products can be up to ten grams lower in saturated fat than their red meat alternatives (pork, beef, lamb, veal, and mutton).^2,3,4 Saturated fat raises the amount of cholesterol in blood, increasing the risk of developing heart disease.⁵ Therefore, eating less red meat can be protective against heart disease. Cutting back on high fat proteins has also been shown to protect against obesity and certain types of cancer, such as colorectal cancer.²

This does not mean that you need to avoid red meat all together. Simply choose lean options as often as possible and eat smaller portions. Red meats that are considered lean and, therefore, have less saturated fat are labeled as choice, select, sirloin, roast, round, loin, or steak.^6,7 A one-pound package of extra-lean or lean ground meat can make about four hamburgers and each will have approximately five to ten grams of fat.⁶ Most burgers are larger than this and consequently have higher amounts of saturated fat. A serving of meat, which is about three to four ounces, is equivalent to a deck of cards or the palm of your hand.

Another way to increase lean protein variety is by including vegetarian and fish sources of protein. Beans and legumes are excellent sources of protein. They are low in sodium and fat, and high in protein and fiber. Fish contain omega-3 fatty acids, which have been shown to be heart protective.⁸ Research recommends eating eight ounces of fish a week, or about two servings.⁹ Nuts and seeds contain protein and monounsaturated fats, another type of fat that is beneficial for heart health.¹⁰ The DASH diet recommends eating four to five servings, about 1/3 cup each, per week.¹¹ Variety also ensures that you get the essential nutrients that your body needs in order to stay healthy.⁹

Americans have been choosing leaner proteins and reaping the benefits of diets lower in saturated fat. However, red meat certainly has not disappeared from dinner plates, nor does it have to. Choose lean options when possible and aim for a variety of proteins throughout the week for added health benefits.

References:

1.     Interagency Agricultural Projections Committee. USDA agricultural projections to 2025. United States Department of Agriculture. http://www.usda.gov/oce/commodity/projections/USDA_Agricultural_Projections_to_2025.pdf. Published February 2016. Accessed November 2016.

2.     Daniel CR, Cross AJ, Koebnick C, Sinha R. Trends in meat consumption in the United States. Public Health Nutr. 2011;14(4):575-583.

3.     United States Department of Agriculture, Agricultural Research Service: National nutrient database for standard reference release 28: Basic report: 05011, chicken, broilers or fryers, meat only, raw. https://ndb.nal.usda.gov/ndb/foods/show/834?manu=&fgcd=&ds=. Accessed December 2016.

4.     United States Department of Agriculture, Agricultural Research Service: National nutrient database for standard reference release 28: Basic report: 13330, beef, variety meats and by-products, mechanically separated beef, raw. https://ndb.nal.usda.gov/ndb/foods/show/3792?fgcd=&manu=&lfacet=&format=&count=&max=50&offset=&sort=default&order=asc&qlookup=beef&ds=. Accessed December 2016. 

5.     American Heart Association. Saturated Fats. American Heart Association. http://www.heart.org/HEARTORG/HealthyLiving/HealthyEating/Nutrition/Saturated-Fats_UCM_301110_Article.jsp#.V-M3TNyksWU. Updated September 12, 2016. Accessed September 2016.

6.     Mayo Clinic. Healthy lifestyle: Nutrition and healthy eating. Mayo Clinic. http://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/cuts-of-beef/art-20043833. Accessed October 2016. 

7.     American Heart Association. Eat more chicken, fish and beans. American Heart Association. http://www.heart.org/HEARTORG/HealthyLiving/HealthyEating/Nutrition/Eat-More-Chicken-Fish-and-Beans_UCM_320278_Article.jsp#.V-M3ptyksWU. Updated December 2, 2014. Accessed September 2016. 

8.     The Nutrition Source. Omega-3 fatty acids: An essential contribution. Harvard T.H. Chan School of Public Health. https://www.hsph.harvard.edu/nutritionsource/omega-3-fats/. Accessed October 2016. 

9.     United States Department of Health and Human Services, United States Department of Agriculture. Dietary guidelines: 2015-2020. United States Department of Health and Human Services, United States Department of Agriculture. https://health.gov/dietaryguidelines/2015/guidelines/acknowledgments/. Accessed September 2016. 

10.  American Heart Association. Monounsaturated fats. American Heart Association. http://www.heart.org/HEARTORG/HealthyLiving/HealthyEating/Nutrition/Monounsaturated-Fats_UCM_301460_Article.jsp#.V_Q5ZpMrKRs. Updated September 16, 2016. Accessed October 2016.

11.  Mayo Clinic. DASH diet: Healthy eating to lower your blood pressure. http://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/dash-diet/art-20048456. Published April 8,2016. Accessed December 2016. 

12.  Liebman, B. The changing American diet. Nutrition in Action. September, 2013:10-11. Print.

13.  Picture source: unsplash.com

Do Calcium Supplements Cause Heart Disease?

 

Submitted by Amy Sercel MS RD CD

Edited By Marcia Bristow MS RCN CSSD CD

It was all over the news: a study published in the Journal of the American Heart Association found that “calcium supplements are bad for your heart”¹ and people should avoid taking them.  This is pretty scary considering that almost half of American adults take some type of calcium supplement.^2,3 Before you stop taking your supplement altogether, remember that this is only one study and that the media tends to exaggerate scientific findings to spark the most interest in their stories. 

The researchers looked at data from 2,742 people who participated in the Multi-Ethnic Study of Atherosclerosis.  They believed that taking calcium supplements could cause calcium to be deposited in the arteries, causing the arteries to harden and leading to heart disease.  The results are complicated.

• For the participants who already had calcium in their arteries at the beginning of the study, taking supplements did not affect their risk of heart disease.⁴
• People who had the lowest total calcium intake and took supplements were at the highest risk for developing heart disease.^2,4 
• People with the highest calcium intake (more than 1,400 mg per day from either food or supplements) had the lowest risk of developing heart disease.^2,3
• Regardless of total calcium intake, people who took supplements were 22% more likely to develop heart disease than those who did not.^2,3

It’s important to note that this study only found a correlation between supplements and heart disease.  A correlation or association occurs when two things change at the same time but may not be related.   For example, there may be a correlation between ice cream sales and shark attacks during the summer, but that does not mean buying ice cream will result in a shark attack.  On the other hand, causation occurs when one event leads to another and can only be proved by randomized trials.  This study compared calcium supplementation with accumulation of calcium in the arteries and did not involve giving people calcium supplements to see whether they developed heart disease.  Therefore, the findings cannot actually prove that taking calcium supplements causes heart disease.  

 It’s possible that the people who took supplements had a lower quality diet overall or another lifestyle factor that contributed to their risk for heart disease.  This study’s findings also conflict with other research.  An expert panel of Tufts University researchers examined 165 peer-reviewed articles and 11 systematic reviews on the topic and found that there is no relationship between calcium supplements and heart disease.⁵ In fact, a study of 38,772 women found that a calcium intake below 696 mg per day was associated with an increased risk of heart disease and that calcium supplements lowered that risk.^6,7

So, what does this all mean?  Although this one study found a relationship between calcium supplements and heart disease, the overall body of literature does not agree.  While it is always a good idea to get your nutrients from food sources, taking calcium supplements to meet your needs is a safe way to make up any deficits in your diet.^4,5 It’s important to make sure you are meeting your needs for calcium each day to maintain bone, nerve, and muscle health.  The recommended daily intake of calcium is 1,200 mg for women and 1,000 mg for men.  Foods rich in calcium, such as dairy products, leafy green vegetables, fortified cereals, and fatty fish canned with bones, are valuable parts of a healthy meal plan and are also good sources of other essential nutrients.  If you are worried about your calcium intake, talk to a Registered Dietitian to see if you should make any dietary changes.

References:

1.         Calcium supplements could increase risk of heart disease, new study finds - The Washington Post. https://www.washingtonpost.com/national/health-science/calcium-supplements-may-raise-risk-of-heart-disease/2016/10/17/a80285fe-9215-11e6-9c52-0b10449e33c4_story.html?utm_term=.2050a130d1aa. Accessed December 1, 2016.

2.         Anderson JJB, Kruszka B, Delaney JAC, et al. Calcium Intake From Diet and Supplements and the Risk of Coronary Artery Calcification and its Progression Among Older Adults: 10‐Year Follow‐up of the Multi‐Ethnic Study of Atherosclerosis (MESA). J Am Heart Assoc. 2016;5(10):e003815. doi:10.1161/JAHA.116.003815.

3.         Calcium supplements may damage the heart. ScienceDaily. https://www.sciencedaily.com/releases/2016/10/161011182621.htm. Accessed December 1, 2016.

4.         Schardt D. See the news that calcium supplements are bad for your heart? NutritionAction.com. October 2016. http://www.nutritionaction.com/daily/dietary-supplements/see-the-news-that-calcium-supplements-are-bad-for-your-heart/. Accessed November 22, 2016.

5.         Kopecky SL, Bauer DC, Gulati M, et al. Lack of Evidence Linking Calcium With or Without Vitamin D Supplementation to Cardiovascular Disease in Generally Healthy Adults: A Clinical Guideline From the National Osteoporosis Foundation and the American Society for Preventive Cardiology. Ann Intern Med. October 2016. doi:10.7326/M16-1743.

6.         Vitamin D and calcium: a systematic review of health outcomes. http://www.crd.york.ac.uk/CRDWeb/ShowRecord.asp?ID=32010001604. Accessed November 22, 2016.

7.         Mursu J, Robien K, Harnack LJ, Park K, Jacobs DR. Dietary supplements and mortality in older women: the Iowa Women’s Health Study. Arch Intern Med. 2011;171(18):1625-1633. doi:10.1001/archinternmed.2011.445.

Shifting the Fatty Acid Ratio

 

Submitted By Amy Sercel MS RD CD

Edited By Marcia Bristow MS RDN CSSD CD

From boxes of cereal to frozen dinners, the food we eat today is definitely not the same as the food our ancestors ate.  One of the most striking differences is in the types of unsaturated fat we eat.  While our ancestors used to eat about an equal amount of omega-3 fatty acids and omega-6 fatty acids, today we eat between 10-20 times more omega-6 fatty acids than omega-3’s.  Today’s foods contain more omega-6 fatty acids than they used to because food processing methods have changed.  Omega-6 fatty acids are found in corn, cottonseed, and soybean oils, which are common ingredients in packaged foods.  At the same time, livestock is raised on a diet of grains, corn, and soy, which results in meat and dairy products higher in omega-6 fatty acids. This dietary shift may be an underlying cause of weight gain, heart disease, and diabetes.^1–3

Omega-3 and omega-6 fatty acids are both unsaturated fats that are essential for health.  Your body can’t make them, so you need to get them from food.  You’re probably familiar with omega-3’s because of their reputation for reducing the risk of heart disease.  They’re found in olive oil, canola oil, flaxseeds, walnuts, chia, and cold-water fish like salmon.² When there are more omega-6’s than omega-3’s in your diet, omega-6 fatty acids will replace omega-3’s in your cells.² Unfortunately, omega-6’s are more likely to become damaged than omega-3’s, which can lead to inflammation, increased blood pressure, and heart disease.¹ Omega-6’s also promote the storage of fat throughout the body and in the liver, potentially resulting in weight gain and decreased liver function.^1,3

The anti-inflammatory properties of omega-3 fatty acids appear to counteract the negative health effects of omega-6’s.  In one study, women with more omega-3 fatty acids in their cells were less likely to gain weight after ten years.² Additionally, people who took daily 3-gram supplements of omega-3 fatty acids had a smaller waist circumference and lower blood pressure than those who did not at the end of a 20-week study.⁴

If you’re interested in shifting the ratio of unsaturated fatty acids in your diet, start by replacing some sources of omega-6 fatty acids with omega-3’s.  It’s important not to eat more calories than you need, especially if you are trying to lose weight; eating more calories from foods high in omega-3 fatty acids will still result in weight gain unless you reduce calories from another type of food.  Try snacking on some fruit and walnuts instead of a processed food.  You could also look for grass-fed beef instead of beef raised on grains, and eat cold-water fish once or twice per week.¹ Combining these changes with daily physical activity is a great step towards weight loss and a healthier lifestyle.

References:

1.         Balancing Act. http://www.todaysdietitian.com/newarchives/040113p38.shtml. Accessed November 15, 2016.

2.         Simopoulos AP, DiNicolantonio JJ. The importance of a balanced ω-6 to ω-3 ratio in the prevention and management of obesity. Open Heart. 2016;3(2):e000385. doi:10.1136/openhrt-2015-000385.

3.         Simopoulos AP. An Increase in the Omega-6/Omega-3 Fatty Acid Ratio Increases the Risk for Obesity. Nutrients. 2016;8(3):128. doi:10.3390/nu8030128.

4.         de Camargo Talon L, de Oliveira EP, Moreto F, Portero-McLellan KC, Burini RC. Omega-3 fatty acids supplementation decreases metabolic syndrome prevalence after lifestyle modification program. J Funct Foods. 2015;19:922-928.