Wednesday, February 16, 2005

The anti-juice campaign?

OK, this is ridiculous. In less than a week, CNN has featured not one, but two articles bashing fruit juice for children. The first CNN article focused on a recent journal article, and I've already described how deceptive that report was. The second article, "Doctors say kids should lay off juice", doesn't focus on any particular studies, but instead uses quotes from three doctors to show how awful juice is for children. The introduction of this recent article is just about as good as the introduction to their first article:
"Soda in a sippy cup?

"Most parents wouldn't dream of it. But researchers say that when a baby's bottle or cup is filled with juice -- even the 100 percent, all-natural, no-sugar-added stuff -- parents might as well be pouring Pepsi.
This is at best sensationalist, and at worst completely inaccurate. Those who've read my recent review of Welsh et al.'s paper (2004; the subject of the first CNN article) know that the study found differences between juice and other sweet drinks, and didn't even show that sweet drinks were bad for all children.

More specifically, Welsh et al. found that children's consumption of any sweet drinks (soda, juice, Kool Aid, etc.) was related to the likelihood of overweight and at-risk-of-overweight children remaining or becoming overweight, but was not associated with normal-weight or underweight children becoming overweight. When Welsh et al. looked at just 100% juice consumption, they found no statistically significant associations between children's weight and juice consumption for any weight class of child. So, not only is there not a strong link between sweet drinks and weight gain (normal-weight children didn't demonstrably gain weight), but the study also shows that there is some quantifiable difference between juice and other sweet drinks. Thus, pouring a glass of juice is not the same thing as pouring a glass of Pepsi.

The article only gets worse:
"'All of these beverages are largely the same. They are 100 percent sugar,' Dr. David Ludwig, an expert on pediatric obesity at Children's Hospital Boston, said recently. 'Juice is only minimally better than soda.'

"The trouble is that parents who are quick to limit a child's soft drink consumption often overlook or even encourage juice indulgence thanks to the beverage's good-for-you image.

"But that image can be overstated. Though healthy in moderation, juice essentially is water and sugar. In fact, a 12-ounce bottle of grape soda has 159 calories. The same amount of unsweetened grape juice packs 228 calories.
There are a number of problems with the statements above; I'll go through them one at a time.

1) Grape juice is not 100% sugar. In fact, its macronutrient breakdown is 96% carbohydrate (including 0.3 g of fiber in an 8oz serving), 3% protein, and 1% fat, though actually a glass of grape juice is mostly water (~84%). Grape soda's macronutrient breakdown, on the other hand, is indeed 100% carbohydrate.

2) CNN got their Calorie counts correct, but they failed to mention that grape juice is one of the highest-Calorie 100% juices available. 12 ounces of orange juice and 12 ounces of grapefruit juice have 168 and 152 calories respectively, right in the range of grape soda (see Table 1).

3) A major difference between fruit juice and soda is that 100% fruit juices have many vitamins and other nutrients, while soda does not. All four fruit juices I acquired nutritional data for (see Table 1) have decent amounts of many vitamins (e.g. thiamin, riboflavin, niacin, vitamin B6) and minerals (e.g. magnesium, phosphorous, potassium), whereas the grape soda had no vitamins and very few minerals (and was lacking in all the items I've listed here). See Table 1 below for a full comparison of the nutrients in soda versus the nutrients in a number of common juices.

The CNN article also oversimplifies the regulation of hunger:
"Part of the problem is that the calories in juice are so concentrated. Just half a cup (4 ounces) of apple juice has 60 calories, the same as a whole apple, but without the fiber that makes fruit filling."
This post is not the place to delve into the regulation of hunger and feeding behavior in humans, but suffice to say that there are plenty of studies showing that hunger is regulated by a far more complicated system than one that simply measures the amount of fiber in the intestines at any one time, as this statement implies.

The article also has a sidebar, which gives this deceptively titled summary of the juice literature:
Science: Contrary to the healthy image of unsweetened juices, research increasingly links sweet drinks of all kinds to childhood obesity. Doctors say juice isn't much better than soda.
Reason: Like soda, juice is mostly water and sugar, and it doesn't have the fiber of whole fruit.
Advice: Children under 6 months should never have juice, and there's no nutritional reason to give it to kids before their first birthday. Kids under 6 can be allowed about a half-cup; plump children should avoid it altogether.
Source: Associated Press
The "science" portion of the sidebar yet again confounds juice with all sweet drinks (a common problem in both CNN articles). Notice also that there's not a single reference in the sidebar (there are no references in the rest of the article either). What studies are they citing? My guess is that the article's author is probably including the 10,000-child Welsh et al. study in their research category, which, as I've said above, doesn't support their implications that juice causes overweight in children.

Where can we find actual research into the topic of juice consumption and overweight? The Welsh et al. introduction nicely summarizes some of the research into sweet drinks' and juices' effects on childhood weight. Welsh et al. list six studies that all show a link between sweetened drinks (sodas, Kool Aid, etc.) and overweight in humans. However, Welsh et al.'s section on the link between 100% juice and overweight paints a less-certain picture:
"Among preschool children, previous studies have focused on the association between consumption of fruit juice and overweight. Dennison et al [1997], in a cross-sectional study, found that children who were aged 2 and 5 years who consumed ≥12 oz/day of fruit juice were more likely (32% vs 9%) to be obese (BMI ≥90th percentile) than those who consumed less. However, longitudinal studies reported by Skinner et al [Skinner et al. 1999 and Skinner and Carruth 2001] and Alexy et al [1999] suggested that juice consumption has no association with the incidence of overweight."
So, based on this introduction, we have one paper that shows a link between juice consumption and overweight, and four papers (including Welsh et al.) that show no association between juice consumption and overweight. In fact, the one study (Dennison et al. 1997) cited as showing a link between drinking juice and overweight did not take total Calorie intake into account, so it is possible that this observed link between obesity and juice consumption is solely due to overweight children consuming more Calories, some of which came from juice. In sum, these studies constitute good evidence that juice by itself does not lead to overweight, and most certainly do not justify the statement that juice is equivalent to soda. In fact, one of the papers (Skinner and Carruth 2001) found that "As juice consumption decreased, intakes of less nutritious beverages increased", indicating that parents are most likely not substituting milk or water for juice, as the CNN articles suggest they should.

But ignoring the deceptive writing and possibly bad science, the article does have some good points. The article suggests that parents should have children drink milk or water instead of juice and sweet drinks. Milk is certainly a very healthful drink for children, and it's hard to go wrong with water. The pediatric association's recommendation not to give nursing children juice also makes perfect sense; juice is no substitute for breast milk or formula.

However, the article fails to clearly delineate a number of key conclusions that can be drawn based on the literature summarized above.

1) If your child is overweight, it may be worthwhile to look at how many Calories they're getting from juice. If the child is getting a large number of Calories from juice, then consider switching the child to drinking milk or water. However, the same goes for any food or drink that overweight children are consuming, so there's no reason to single out juice for special attention (e.g. drinking milk in excess could easily lead to overweight).

2) 100% juice in moderation will not harm your child, so if your child enjoys juice there's absolutely no reason to cut it out from their diet. Even for overweight children, the Welsh et al. study shows no statistically significant relationship between juice consumption and remaining overweight, and for normal or underweight children there's not even a statistically significant relationship between consumption of all sweet drinks and becoming overweight.

3) 100% juice is a more nutritious choice for children than juice "drinks", juice "beverages", Kool Aid, lemonade, or soda. So, if a parent has a choice between any one of those drinks, they should almost always choose 100% juice over the alternatives. About the only more nutritious drink for a child is milk, and the ideal low-calorie drink for a child is water.

Unfortunately, parents don't get these messages from the two CNN articles, and thus it's likely that they'll just settle on soda or Kool Aid as drinks for their children, since juice is more expensive and, after all, just "soda in a sippy cup."

Table 1: Nutrition data for 12 ounces of four 100% fruit juices and grape soda. Units for most numbers are in the column to the left, and percent daily values (%DV), where available, are in parentheses after each value. %DV are for "adults or children aged 4 or older, and are based on a 2000 Calorie reference diet." (Data for canned or bottled grape juice, orange juice from concentrate, pineapple juice from concentrate, grapefruit juice from concentrate, and grape soda)

Orange juice (%DV) Pineapple juice (%DV) Grapefruit juice (%DV) Grape juice (%DV) Grape soda (%DV)
Calories 168 195 151.5 231 160
%carbs 94% 97% 92% 96% 100%
%fat 1% 0 3% 1% 0
%protein 5% 3% 5% 3% 0

Protein 2.55 g (4.5%) 1.5 g (3%) 2.1 g (4.5%) 2.1 g (4.5%) 0 g
Tryptophan (mg) 7.5 - -
Threonine (mg) 29.85 - - 60.75 0
Isoleucine (mg) 26.1 - - 26.55 0
Leucine (mg) 48.6 - - 45.6 0
Lysine (mg) 33.6 - - 37.95 0
Methionine (mg) 11.25 - - 3.75 0
Cystine (mg) - - - - 0
Phenylalanine (mg) 29.85 - - 45.6 0
Tyrosine (mg) 15 - - 11.4 0
Valine (mg) 41.1 - - 37.95 0
Arginine (mg) 168 - - 178.5 0
Histidine (mg) 11.25 - - 26.55 0
Alanine (mg) 52.35 - - 327 0
Aspartic acid (mg) 268.5 - - 83.55 0
Glutamic acid (mg) 119.55 - - 417 0
Glycine (mg) 33.6 - - 45.6 0
Proline (mg) 157.5 - - 60.75 0
Serine (mg) 48.6 - - 49.35 0
Hydroxyproline (mg)
- -


Vitamin A (IU) 399 (7.5%) 37.5 (0%) 33.3 (0%) 30.3 (0%) 0
Retinol (mcg) 0 0 0 0 0
Retinol Activity Equivalent (mcg) 18.75 3.75 0 0 0
Alpha Carotene (mcg) 11.25 0 7.35 0 -
Beta Carotene (mcg) 63.45 22.5 14.85 19.05 -
Beta Cryptoxanthin (mcg) 340.5 0 3.75 0 -
Lycopene (mcg) 0 0 0 0 -
Lutein+Zeaxanthin (mcg) 429 0 37.05 132.9 -
Vitamin C (mg) 145.35 (241.5%) 45 (75%) 124.8 (208.5%) 0.45 (0%) 0
Vitamin D - - - - -
Vitamin E (mg) 0.75 (3%) 0 (0%) 0.15 (0%) 0 (0%) -
Beta Tocopherol (mg) 0 - - 0 -
Gamma Tocopherol (mg) 0.15 - - 0 -
Delta Tocopherol (mg) 0 - - 0 -
Thiamin (mg) 0.3 (19.5%) 0.3 (18%) 0.15 (10.5%) 0.15 (6%) 0
Riboflavin (mg) 0 (4.5%) 0.15 (4.5%) 0.15 (4.5%) 0.15 (9%) 0
Niacin (mg) 0.75 (4.5%) 0.75 (3%) 0.75 (4.5%) 1.05 (4.5%) 0
Vitamin B6 (mg) 0.15 (7.5%) 0.3 (13.5%) 0.15 (7.5%) 0.3 (12%) 0
Folate (mcg) 165 (40.5%) 41.25 (10.5%) 14.85 (3%) 11.4 (3%) 0
Food Folate (mcg) 165 41.25 14.85 11.4 0
Folic Acid (mcg) 0 0 0 0 0
Dietary Folate Equivalents (mcg) 165 41.25 14.85 11.4 0
Vitamin B12 (mcg) 0 0 0 0 0
Pantothenic Acid (mg) 0.6 (6%) 0.45 (4.5%) 0.75 (7.5%) 0.15 (1.5%) 0
Vitamin K (mcg) 0.3 (0%) 1.05 (1.5%) 0 (0%) 1.5 (1.5%) -


Calcium (mg) 33.6 (3%) 41.25 (4.5%) 29.7 (3%) 34.2 (3%) 11.2 (1%)
Iron (mg) 0.3 (1.5%) 1.05 (6%) 0.45 (3%) 0.9 (4.5%) 0.3 (2%)
Magnesium (mg) 37.35 (9%) 33.75 (9%) 40.8 (10.5%) 37.95 (9%) 3.7 (1%)
Phosphorus (mg) 59.7 (6%) 30 (3%) 51.9 (4.5%) 41.7 (4.5%) 0 (0%)
Potassium (mg) 709.5 (21%) 510 (15%) 504 (15%) 501 (15%) 3.7 (0%)
Sodium (mg) 3.75 (0%) 3.75 (0%) 3.75 (0%) 11.4 (0%) 55.8 (2%)
Zinc (mg) 0.15 (1.5%) 0.45 (3%) 0.15 (1.5%) 0.15 (1.5%) 0.3 (2%)
Copper (mg) 0.15 (7.5%) 0.3 (16.5%) 0.15 (6%) 0.15 (6%) 0.1 (4%)
Manganese (mg) 0 (3%) 3.75 (186%) 0 (3%) 1.35 (69%) 0 (2%)
Selenium (mcg) 0.3 (0%) 0.45 (0%) 0.3 (0%) 0.45 (0%) 0 (0)


Alexy U, Sichert-Hellert W, Kersting M, Manz F, Schoch G. 1999. Fruit juice consumption and the prevalence of obesity and short stature in german preschool children: results of the DONALD Study. Dortmund Nutritional and Anthropometrical Longitudinally Designed. J Pediatr Gastroenterol Nutr 29: 343–349 (abstract)

Dennison BA, Rockwell HL, Baker SL. 1997. Excess fruit juice consumption by preschool-aged children is associated with short stature and obesity. Pediatrics: 99 : 15–22 (abstract, PDF)

Skinner JD, Carruth BR, Moran J III, Houck K, Coletta F. 1999. Fruit juice intake is not related to children's growth. Pediatrics 103: 58–64 (abstract, PDF)

Skinner JD, Carruth BR. 2001. A longitudinal study of children's juice intake and growth: the juice controversy revisited. J Am Diet Assoc 101: 432-437 (abstract)

Welsh, JA, ME Cogswell, S Rogers, H Rockett, Z Mei, and LM Grummer-Strawn. 2004. Overweight Among Low-Income Preschool Children Associated With the Consumption of Sweet Drinks: Missouri, 1999–2002. Pediatrics 115: e223-e229. (Abstract, PDF)

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