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By Lori Bricker, MS, RD
A flurry of tea articles appeared in the press recently, so I thought I'd give you the highlights:
A Cup of Coffee OK During Pregnancy
 The American College of Obstetricians and Gynecologists has changed their recommendation regarding caffeine consumption during pregnancy. Formerly, caffeine was considered off-limits since it can cross the placenta, but now the group says up to 200 mg of caffeine per day is unlikely to cause an increased risk of miscarriage or premature delivery. Two recent studies each followed 1000 pregnant women. One study found no increased risk of miscarriage with any amount of caffeine; the other found no increased risk at intakes up to 200 mg per day. Two other studies showed no risk of premature delivery with moderate caffeine intake. So how much is 200 mg? Approximately 12 oz. of coffee, 24-32 oz. of tea, or 6 or 7 dark chocolate bars (please don't eat that many at once!).
Black Tea Compounds Show Anti-Allergy Potential
A new study that used mice shows that theaflavins, the flavanoid found in black tea, reduce a certain type of allergic reaction. The researchers gave mice large doses of theaflavin extract and then subjected them to various allergens (allergy-causing substances). Compared to control mice who were not given the theaflavin, the mice had much lower responses to the allergens. Responses were measured by looking at blood levels of certain markers of inflammation. Keep in mind that a) this study was on mice, not humans; and b) the dose given the mice was rather large (50 mg theaflavins per kg body weight). If a human were to get a comparable dose of theaflavin from tea, it would take between 20-25 cups.
Greater Concentrations of Fluoride in Tea than Once Thought
Researchers at the Medical College of Georgia have come up with a new way to test how much fluoride is in tea, and it's more than we thought. The researchers bought seven brands of black tea from grocery stores and brewed each for 5 minutes in water that did not contain fluoride. While previous methods showed amounts of 1-5 mg fluoride per liter, the new method showed fluoride levels as high as 9 mg per liter (a liter is about a quart, or 4 cups). Although this is not a concern for most tea drinkers, those who drink the most tea, say a gallon or more a day, should be concerned. Too much fluoride over a very long period of time (such as 20 mg per day for at least 10 years) can result in skeletal fluorosis, a condition that can lead to damaged and painful joints. The lead researcher, Dr. Gary Whitford, had seen 4 patients with skeletal fluorosis, and they all drank 1-2 gallons per day of tea for 10-30 years. Dr, Whitford said, “The additional fluoride from drinking two to four cups of tea a day won’t harm anyone; it’s the very heavy tea drinkers who could get in trouble.”
This research specifically discusses black tea. Someone asked me if the same is true for green, oolong, and white tea. I haven't seen any data regarding re-testing the amount of fluoride in other kinds of tea, so I just don't know. It makes sense to me that higher levels would be found there as well, as compared to previous measurements. Green tea has roughly the same amount of fluoride as black tea.
If you are concerned about the fluoride in your tea
- Find out how much fluoride is in your local water supply.
- Use bottled water (or other non-fluoridated water) to brew your tea.
- Don't drink gallons.
- Discuss fluoride with your doctor and dentist and let them know how much tea you drink.
By John Rice, General Manager
I'm always surprised that people who insist on the high quality of loose leaf tea when they intend to drink it hot, assume they have to use bagged tea when they will be drinking it iced. The fact is, using loose leaf tea for iced tea is incredibly simple and fast, and doesn't require much equipment that most kitchens don't already have. A larger infuser, like a 6 cup tea ball or Chelsea reusable cloth tea bag, is probably all you need.
Here is how I make a gallon of the world's best iced tea in ten minutes:
- Fill a large saucepan with about 2 quarts of fresh water and put it on high heat to boil. The exact amount of boiling water isn't critical. I'm a bit of a stickler when it comes to consistency, so I always weigh the tea I use, since it is the only truly accurate way to get the same amount every time. With unflavored or lightly flavored teas, I measure out .70 oz (20 grams) of tea (about 4 tablespoons). With flavored teas that have chunks of anything other than tea (fruit rinds, spices, etc.) I usually use 1 oz (28 grams, or about 5 tablespoons). You may want to adjust to your own tastes. Put your tea in the infuser. In many cases, one 6 cup tea ball should be big enough, but if it seems a bit tight, which it will be with certain teas, split the tea between two of them. Better yet, use a Chelsea reusable cloth tea bag.
- Once the water is boiling, take it off the heat, put the infuser in the water and start your timer. Pull the infuser through the water periodically, to make sure it is getting good exposure to the water. When the time is up, take the infuser out of the water. If you want to add sugar, do it now and stir completely.
- Finally, I pour the hot tea into a gallon pitcher which is about half full of ice. For the clearest tea possible, I set a large colander across the top of the pitcher, put a sheet of sack cloth in the colander and pour the tea through it. Fill the pitcher the rest of the way with tap water and you're good to go. Rinse out your infuser, colander and sack cloth and let them dry for the next time.
I recommend trying any tea you enjoy hot. Impress your friends with a delicious tumbler of your favorite loose leaf tea. You will be surprised how good iced tea can be. Take it easy on the sugar at first. High quality tea deserves to have its flavor come through.
A couple suggestions. It is best if the saucepan is NOT non-stick. That way you can quickly scrub out any residue left by the tea. Also, an electric kettle makes the whole process even faster, since they boil water in significantly less time than the stove top. Any avid tea drinker should have one anyway and they are easy to find at most department stores such as Target. I still use the saucepan to brew the tea, and preheat it a bit while the water is boiling, but I put the infuser in the saucepan and pour the boiling water over it as it sits in the saucepan.
Got a favorite iced tea method of your own? Please share!
By Lori Bricker, MS, RD
I hate giving people answers they don't want to hear. As a tea shop owner, I get a lot of questions about the health effects of tea. Since I have a background in nutrition, I have some insight into how complicated the question really is, so my answers are never what people expect. People ask pretty specific questions, but sadly, the specific answers they want are not available yet.
Here are some really good questions that have no known answers:
• Which tea is the most healthful?
• Which tea has the least caffeine?
• Which tea will cure my [fill in the blank]?
• How much tea should I drink in a day?
The science of tea (Camellia sinensis) is too young to offer definitive answers to these and other popular questions. But there are a lot of studies being done, and many get written up in the popular press. So many, in fact, that it's easy to get the impression that tea is a real cure-all. I'd like to talk about why you should be cautious when you read these articles. For this post, I'll just talk about cohort studies, and another post will discuss research studies.
Here's what you need to know about cohort studies:
- Cohort studies involve large numbers of people (not rats!) who have something in common and following them for several years, then studying data collected during that time and to look for trends in the various outcomes. For example, you might look at everyone born before 1950 in a particular town, and follow them for 15 years to determine the rates of a certain disease. You compare the disease trends with the information the participants give you about their diet, health history, medications, etc.
- Their major strength is that because cohort studies last so long, you can see real outcomes, like death and disease, that you just don't get with shorter experiments.
- The downside is that lots and lots of things happen to the people in your cohort, and you have less control over it than you would in an experiment.
- Cohort studies usually use questionnaires to gather data from the participants. For food and beverage intake data, researchers use a tool called a food frequency questionnaire, which will ask you potentially hundreds of questions such as, "How often do you eat broccoli in a month and what is the serving size?" By the time you get to the end, your mind is mush. Even in a well-designed food frequency tool, self-reported data is only as good as the participants' memories, patience, and honesty.
- Cohort studies usually do not show cause and effect. They show correlations, but they don't tell if one thing caused the other. To illustrate the point, you might notice a correlation between the occurrence of rain the the appearance of umbrellas. Of course, you would be wrong to conclude that umbrellas caused the rain.
Another confounding factor for ANY tea research is that tea preparation methods can affect how concentrated a brew you are consuming, which in theory should affect the results. I might brew an 8 oz. cup of tea for 8 minutes in boiling water using 3 tsp of leaves. You might drag a tea bag through 8 oz. of tepid water and be done. There could be a huge difference in the amount of tea catechins and other active compounds in these two beverages.
Now, of course, the scientists doing this research know all these things, but sometimes these concerns don't get addressed in media stories about the research.
When reading an article in the popular press about a research article involving a cohort:
- Read carefully to see if they use the word, "correlation," and if so, don't misread causation into that.
- Notice details about the cohort itself– is it all women, all men, all people from one country or another, do they have any diseases, what kind of tea do they drink?
- What do they say about the kind of questionnaire used? Was it filled out just once at the beginning or multiple times? Do they tell you what they asked regarding tea consumption?
- Read more than one article about the same research to see if you get a consistent message.
Be aware that it takes mounds of research before you can really say something with confidence. In this online article reporting on a heart disease study that involved tea and coffee, Dr. Frank Hu, professor of nutrition and epidemiology at the Harvard School of Public Health, is quoted as saying,
"Based on current evidence, it is very difficult to come up with an optimum amount of coffee or tea for the general population."
After years of research on tea (and coffee), this is where we are? Yes, and we are likely to be here for a while.
By Lori Bricker, MS, RD
Someone I follow on Twitter asked whether having afternoon tea with a sweet treat would harm her attempts at weight loss. She referenced an article called, Tea Time Calls For Sweet Treat, by Ginna Parsons, who mentions a book she read whose author says she finds that having a 150 calorie treat mid-afternoon helps her not eat too much later on. As a dietitian, I thought I should offer my opinion.
This can be a fine strategy for a number of reasons:
1. Having a reasonable portion of a perceived "treat" each day can help you cope with the otherwise hard facts of dieting. If you continually deny yourself every treat for the sake of your diet, you will set yourself up for a binge episode, which can easily get out of hand. But knowing that you can have a treat everyday is very soothing when you're feeling a bit deprived, and it gives you something to really look forward to.
2. A tea break in the afternoon (with or without food) can provide relief from the mental stress of your day. We all tend to eat more when we feel overwhelmed, so by preventing your stress level from climbing, you can avoid stress-eating later..
3. I have found that when you prevent yourself from getting overly hungry, it can help you eat less at the next meal. This doesn't always work for everyone, however, so you need to see how you do with it. The suggestion in the article of a 150 calorie treat seems reasonable — just enough to make you feel like you had something without blowing it. Make sure to help yourself control portion sizes by only taking to the table what you are allowing yourself to have, otherwise you may be too tempted to have a second helping.
If you're worried that having a treat will make you go over on your allowed calories, burn some extra by taking a brisk walk. A walk of 45 minutes should burn off that treat.
So what should you have? It seems to me that afternoon tea is very suggestive of the proper kind of treat to allow yourself. Typical treats at a casual afternoon tea would be a small scone, a couple of small cookies, or finger sandwiches. Just enough to go with a couple of cups of tea. Here is a list of snacks for roughly 150 calories, in case you'd like some ideas: Sweet, Creamy, and Crunchy Snacks for 150 Calories or Less. Oh, if you put milk or sugar in your tea, don't forget that counts, too.
My preference is for a small slice of homemade banana bread or some similar item. I like to make them myself so I can use whole wheat flour and less sugar and fat to keep it more nutritious.
Do you take afternoon tea? Anyone have any recipes or suggestions they'd like to share?
By Lori Bricker, MS, RD
 As a tea shop owner, one of my worst fears is that customers might inadvertently ruin their tea. This is especially easy for the novice who might not yet know the best practices. Here's a review of the most important things to do for a great tasting cup! I will assume that you have already bought nice loose leaf tea . . .
1. Please use good water. I can't overstate the importance of this. Tea is too delicate a beverage to mask the taste of poor quality water. I found this out first-hand many years ago. I had moved into a new house where the city water left a lot to be desired, but I got used to the taste and didn't think much more about it. I happily made my tea and drank it without complaint. Then I acquired a bottled water service at work, and since I made a lot of tea at work, became accustomed to its taste quickly. Back at home, I noticed my tea tasted awful! Before I realized what the problem was, I threw out a few pots of tea thinking I had let it get too old or something. Then I ordered the same bottled water service for home, and presto! Problem solved
2. Use the proper amount of tea. Most people use too much tea, which can contribute to a bitter or overly strong taste. It is also wasteful. The best way to not use too much tea is to weigh it with a gram scale (start with 2 grams per 6 oz. cup). Using a teaspoon per 6 oz. cup is also about right, but you have to note that some teas are very dense, like Gunpowder Green, while others are rather "fluffy," like Imperial Silver Needles, so you have to adjust.
3. Please pay attention to the brew time. In general, if you let your tea brew too long, it will get bitter. Some people are more sensitive to bitter taste than others, so preferences will vary widely. But it is a good habit to use a timer when brewing your tea. Even an old pro like me can walk away and get distracted only to come back 10 minutes later to an evil tasting cup. If you have your favorite tea all figured out and never ruin it, please watch it with new teas, especially green teas, which sometimes can get bitter even after one minute.
4. Use proper water temperature. The rule of thumb is boiling water for black and herbal; steaming water (i.e., sub-boiling) for green, oolong, and white. Some of the most delicate teas really do best if you use a thermometer to make sure you don't go over a certain temperature.
5. Store tea properly for longest life. The rule of thumb here is "air-tight, dark, and dry." Don't use the refrigerator or freezer, just use any opaque container that has a good seal and keep it away from moisture and odors.
6. Clean your teapot regularly. That buildup on the inside of your teapot will tend to add a bitter quality to your brew. If you drink a wide variety of teas, you should also have a designated teapot for each type, for example, chai, unflavored black, unflavored green, herbals, etc. Especially with ceramic teapots, flavors will be absorbed over time and can be noticeable when drinking a more delicate tea.
7. Experiment!! This is absolutely the only way to tell the best way to prepare any given tea. Keep in mind that preferences will vary from person to person. Some people have very sensitive palates and can tell if a tea has steeped 15 seconds too long, while others are fine with letting a tea bag hang out of their cup for an hour. But if you are interested in improving your cup, try these things:
Use bottled water for a few days, then go back to your tap water and see if you can tell any difference. Good quality tap water is often just fine, but even so, bottled is often an improvement.
Vary the water temperature and brew time, especially if you are noticing bitter tea — keep notes for each tea so you don't forget.
Try different infusers made from different materials. I find people have really strong preferences about whether or not they like metal, plastic, cloth or paper, and often it is because of the taste.
Got a story about how you brew your tea? Please share — we can all learn from each other!
Frequently we find well-written articles explaining some new research about tea. We usually add them to the Links section of the blog (lower right), but the articles are hard to find there, so we will start posting links to them here so they are more obvious. Here are the latest:
Thanks to everyone who submitted an entry for our contest! We have decided we like “A Little Tease” — thank you, Carol, and congratulations! You have won a quarterly Tea of the Month Club! (I’ll contact you for details.)
With our current newsletter, we’re starting a new limited-time offer tea special — here’s how it works: Every two weeks, when we put out a newsletter, we will feature a brand new tea, of which we will have a finite supply. When it is gone, it is gone for good, and we will offer another special with the next newsletter. These tea specials will be available only in 2-oz. and 4-oz. packages, so the product page will look a bit different. You’ll select which size you want, either 2 oz. or 4 oz., then in the Quantity field you enter a “1″ if you want one bag, “2″ for two bags, etc. Sorry, no samples are available of these — what would be the point? They’ll be sold out by the time you taste it! </i>
But — We don’t know what to call this new “special” of ours! We’ve racked our brains and don’t like any of our ideas . . . So we’re asking for your help! Please submit your suggestions for what to name our tea special as comments to this post. We’ll review the submissions and announce the winner in the next newsletter — the winner will receive a Quarterly Tea of the Month Club!! Make sure you enter a valid email address so we can let you know you’ve won!
Our first offering is Madras Fusion Green Chai – like a trip around the Orient. Sultry notes of hot malabar spice mellowed by an exceptional Japanese Sencha green tea. A lightly flavored chai with a subtle peppery taste and pleasant aroma. Please note, Sencha tea is very delicate, so brew according to these directions: Use one tsp leaves per cup and brew in steaming (not boiling) water for one minute.
You will be able to find the “tea special” on its own page, which is listed on our category tree on the left side of any page of the site. Until you come up with something better, it will say “Tea Special”!
By Lori Bricker, MS, RD
 Although not as popular in the United States, it is quite common in Britain to add milk to black tea. Some research has shown that this practice may interfere with the antioxidants in black tea, but the results have been inconsistent. In a study just published in the British journal Nutrition Research, researchers examined five brands of British black tea with the addition of 10, 15, and 20 mL (for reference, one fluid ounce is roughly 28 mL) of whole, low-fat, and skim cow’s milk to 200-mL of brewed tea (about 7 oz.). They found that skim milk decreased the antioxidant capacity of the tea significantly more than either whole milk or low-fat milk. The authors conclude that “black tea is a valuable source of antioxidants and that the effect of milk on the total antioxidant capacity may be related to the fat content of the milk.”
Source: Nutrition Research Volume 30, Issue 1, January 2010, Pages 14-20.
doi: 10.1016/j.nutres.2009.11.005
By Lori Bricker, MS, RD
 There has been so much media hype over green tea and weight loss in the last couple of years that a lot of consumers are becoming very annoyed with what they perceive as slick marketing or outright lies. It is extremely common, especially on the Internet, to find all kinds of “too good to be true” health claims for tea, particularly as it pertains to weight control, a topic of interest to so many. As is frequently the case with exaggerated nutrition claims, there may be some truth behind the hype. So how much can you really depend on green tea to help you slim down? A new review published in The American Journal of Clinical Nutrition demonstrates how complicated this issue is and suggests that green tea is no magic bullet.
The authors of the paper searched for recent studies that had evaluated the effects of green tea catechins, both with caffeine and without, on body weight, BMI (body mass index), waist circumference, and waist-to-hip ratio. To be included in the review, the studies had to be randomized and had to meet validity criteria as determined by use of the American Dietetic Association Research Design and Implementation Checklist. This means that the research was, for example, bias-free, provided a clear statement of the research question, and used appropriate statistical analysis, among other things.
Fifteen research studies met these criteria and were evaluated in this paper. The studies fell into three groups: In seven studies, green tea catechins with caffeine were compared to caffeine-matched controls (we’ll call these Group 1); in six studies, green tea catechins with caffeine were compared to caffeine-free controls (Group 2); and in two studies, caffeine-free green tea catechins were compared to caffeine-free controls (Group 3).
They found the following:
- For Group 1, doses of green tea catechins of 583-714 mg/day over a median of 12 weeks had a statistically significant benefit on BMI, body weight, and waist circumference, but no effect on waist-to-hip ratio.
- For Group 2, green tea catechin intake of 141-1207 mg/day significantly reduced body weight, but had no effect on the other parameters.
- For Group 3, (green tea catechin intake of 282-548 mg/day) there were no significant changes in any of the parameters.
So, off-hand, it looks promising with 2 groups showing “statistically significant” changes in the observed parameters. But here are some things to note:
- Just because a result is statistically significant doesn’t mean it is a big difference; it just means it is unlikely to be caused by chance. For the statistically significant weight loss results observed for Group 1, the amount of weight lost averaged just 3 pounds over 12 weeks for the tea group compared to the control group. That’s something, but it is not like these people lost 10 or 20 pounds in a two weeks by ingesting green tea catechins. For Group 2, the results were even less impressive at an average of <1 pound.
- On a similar note, the authors pointed out that the waist circumference measurements, although reduced by statistically significant amounts for Group 1 (an average of <2cm), practically speaking could have occurred as part of normal measurement error.
- How much green tea catechin were the subjects consuming? The studies evaluated here used varying amounts of green tea catechin, the equivalent of roughly 1-8 cups of tea per day. This makes it very difficult to generalize, and the authors noted they were unable to determine if the effects of green tea catechin were dose-dependent.
- There are also several different green tea catechins, and their specific effects are not fully understood. Some studies reviewed here specified which catechins were given, but others did not.
- The authors also noted that the ingestion of green tea catechins with or without food can affect its absorption (it is increased on an empty stomach), and these studies were inconsistent with respect to when catechins were given to the subjects.
- The populations studied in these trials also varied and included children, men only, postmenopausal women, healthy adults, and adults with various conditions (such as obesity, diabetes, high cholesterol). The authors pointed out that they were unable to say which of these populations might benefit the most from the green tea catechins.
- Group 3 only contains 2 studies, so perhaps we shouldn’t generalize too much about decaffeinated green tea catechins.
- Something to keep in mind in general when looking at tea studies is that how the tea is brewed can effect the quantities of catechin present in the final beverage, so that is often an unknown factor. I also wonder if green tea catechin in capsule form has the same effects as that in brewed tea? This question is not typically addressed.
The authors concluded that the observed reductions in weight loss and other parameters, although statistically significant in some cases, practically speaking are not all that important. As a registered dietitian, if I were counseling someone on a weight loss plan, I would suggest drinking green tea if they like it (why not?), but I certainly would not make it a requirement and would explain that, while it appears to aid in weight loss a bit, it won’t have a dramatic effect. Changing your overall diet to include more vegetables, fruits, whole grains, and fiber while getting plenty of exercise will do far more than green tea.
Source: Phung, O.J., et. al. Effect of green tea catechins with or without caffeine on anthropometric measures: a systematic review and meta-analysis. Am J Clin Nutr 2010;91:73-81.
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