Health » PB&J Campaign Blog

Study: Peanut Butter Fills You Up, Not Out

Lots of studies show that eating nuts–in moderation; a small serving a day–helps you lose weight, even though nuts are calorie-dense and high-fat. (Note that peanuts are technically legumes, but from a nutritional and culinary standpoint they are like nuts.)

Some researchers surmised that there were two mechanisms that could explain the “weight maintenance through nuts” phenomenon:

The “pistachio principle” (which could just as well be called the “peanut principle”): Shelling and crunching on nuts not only burns calories, but slows down the pace of eating.
Some portion of consumed nuts remain intact and pass through the body.

So what about peanut butter? With peanut butter there are no shells, and with smooth peanut butter specifically there is no chance of undigested peanut pieces passing through the system.

A recent study published in the British Journal of Nutrition set out to answer this question. And it found that consuming smooth peanut butter had effects that were about the same as those from consuming nuts. Test subjects who ate a small serving of peanut butter each day kept their weight in check–and also their good cholesterol went up an their bad cholesterol went down.

Granted, there are some limitations with this study: It had a fairly small sample size, it ran for only one month, and the daily amount of peanut butter was a single modest serving. Still, the implications are very good, and it’s not the first study to show positive impacts from peanut butter.

Since there is no “pistachio effect’ or undigested peanut remnants when eating peanut butter, what accounts for its ability to be high-calorie and high-fat yet not contribute to weight gain?

Research points to two factors:

Nuts and peanut butter have a satiating effect. After eating these foods, we’re filled up for a while and eat less during that time.
Nuts increase our metabolism. So we burn up ingested calories more efficiently when we eat nuts (and presumably peanut butter).

For a nicely put together–and entertaining–summary of this subject, watch these four short videos by Michael Greger, M.D.:

Solving the Mystery of the Missing Calories

Testing the Pistachio Principle

Testing the Dietary Compensation Theory

Testing the Fat Burning Theory

Each video references recent published clinical studies.

Kathy Freston: Calorie-Rich Nuts Help You Lose Weight

Kathy Freston, author of Veganist (a New York Times best-seller), The Lean, and other books, gave a nice plug for nuts the other day in her e-newsletter, “The Daily Lean”:

“Yes, nuts are packed with calories, but they are also packed with nutrition. And they fill you up, thereby ‘crowding out’ room in your belly for high-calorie, nutrient-poor foods. A body of research shows that eating nuts in moderation actually helps you lose weight…They also appear to boost our metabolism, meaning when we eat nuts we burn more of our own fat to compensate.”

Though technically a legume rather than a nut, from a dietary standpoint peanuts fall into this same group: they’re nutrient-dense and filling.

Although it’s possible to have too much of a good thing (and really, any healthy food eventually has upper limits), a PB&J sandwich, almonds with your green beans, or walnuts in your salad each each day is not only eco-friendly but waistline-friendly.

Peanut Butter May Help Lower Risk of Diabetes and Heart Disease

It’s great when earth-friendly habits also yield personal health dividends. Check out this good news for PB&J lovers:

Researchers from the Harvard School of Public Health have found that women who consume nuts or peanut butter five times per week or more, significantly lowered their risk for type 2 diabetes compared to those who never or rarely ate nuts or peanut butter. The reduced risk was independent of known risk factors for type 2 diabetes, such as body mass index (BMI), family history of diabetes, physical activity, smoking, alcohol use, and dietary factors. The findings appear in the November 27, 2002 issue of the Journal of the American Medical Association.

Here’s the link to the full article, and here’s a link to the study.

The study involved over 80,000 women. Here’s one of our favorite sentences from the article:

The researchers also found that women in the study who frequently ate peanut butter reduced their risk for type 2 diabetes almost 20 percent compared to women in the study who rarely ate peanut butter.

In a related article from Harvard, Walter C. Willett, M.D., Professor of Nutrition, points out that peanut butter contains “good fat,” fiber, and other nutrients, and that “numerous studies have shown that people who regularly include nuts or peanut butter in their diets are less likely to develop heart disease or type 2 diabetes than those who rarely eat nuts.”

What about PB&J sandwiches in particular? Healthy it up with whole-grain bread and all-fruit jelly. Or take it a step further. If an apple a day keeps the doctor away and daily peanut butter keeps heart disease and diabetes at bay, just think what the two can do together. Try apple slices and peanut butter for a healthy snack, or a peanut butter and apple slices sandwich.

Which reminds us…coming up soon we’ll have some posts in which we ask we ask you to share your favorite variations of PB&J sandwiches.

PB&J = Better Health and Less Nasty Bacteria?

The PB&J Campaign is all about the environmental benefits of eating a plant-based meal like a PB&J (but it does not have to be a PB&J – check out our links to recipes for lots of ideas). These benefits include conserving land and water, cutting pollution, and fighting global warming, but there are also potential health benefits. Of course a heap of french fries counts as a plant-based meal, but assuming you pick more healthful meals, those additional plant-based meals might make you healthier. Some people get worried about getting enough protein, iron, vitamin B12, and other micronutrients, but it turns out that even people who go all the way and end up vegetarian can be pretty healthy, implying that more moderate eating lower on the food chain can’t really hurt.

Treehugger reported on one new study pointing in that direction and wrapped up other recent research on the topic. More ominous, another study documented some nasty bacteria living on about half of all meat sold in the USA. Of course there are still occasionally disease outbreaks from vegetables like spinach and (gasp) even peanut butter, but eating more healthful, plant-based meals is probably generally a nice way to avoid these bacteria.

A Place on the Food Pyramid

The PB&J Campaign focuses on the meal as the unit of action – that eating a plant-based meal like a PB&J Campaign cuts air and water pollution, saves land and water, and helps fight global warming. One meal probably won’t make a big difference on your overall health one way or the other, but if you start getting into the habit of eating lower on the food chain (and we’d love it if you did), eating that more-plant-based diet will probably be good for you, especially if you focus on legumes like peanuts and beans, whole grains, and fruits and vegetables (by contrast a solid diet of tater tots, though incredibly resource-efficient, might not work out so well for you). Some people get concerned about eating enough protein, but since American’s eat about twice as much protein as we actually need, and since foods like peanuts, beans and whole grains already have plenty of protein, you don’t have to worry about that unless you almost completely cut out animal products, and even then you should be fine with a little bit of education and careful eating (for example see the Ultimate Vegan Guide if you’re contemplating going all the way).

Dietitians have noted this for a long time, but for the first time the USDA is explicitly recognizing it in our country’s dietary guidelines (in particular see pages 45 and 52). This is exciting news, that there is official recognition that eating a more plant-based diet is not only not bad for you, but as the guidelines note, is generally good for you.

Eat Like a Chinese Peasant

As you start eating a few more plant-based meals here and there – maybe a PB&J, a falafel for lunch, veg chili for dinner, more oatmeal for breakfast – you might start wondering how this will affect your health. The PB&J Campaign does not focus on promoting the health benefits of eating lower on the food chain (see our friends over at Meatless Monday for even more on that front), but every now and then we do like to remind people that in addition to fighting pollution and climate change, cutting water use, and saving land, eating a more plant-based diet is probably pretty good for you.

The China Study is a book that’s caught fire recently, looking at how peasants in China, who eat a predominantly plant-based diet (here’s to all that tofu!) with lots of whole foods and vegetables, are in many ways healthier than we Westerners who pack in the meat, cheese, and processed carbs with very little veggies. Recently the NY Times Well Blog interviewed the book’s author, who makes a strong health argument for shifting hard down the food chain.

Eat PB&Js or DIE! (slight exaggeration)

At the PB&J Campaign we’ve covered the health benefits of shifting to a more plant-based diet, though primarily as a nice side point, as in ‘look how much you’re helping the environment (saving water, land, and other resources, reducing pollution, fighting global warming) each time you have a plant-based meal like a PB&J, AND it can be good for you too!’ After all, this is an environmental project. Still, sometimes a headline comes along and just begs to be covered.

Oxford University’s British Heart Foundation Health Promotion Research Group crunched the numbers on the health problems associated with eating a lot of meat (in a study funded by an environmental group, Friends of the Earth), and they figured that in the UK about 45,000 lives could be saved if everyone cut back to only three meat-based meals per week. We’re not sure exactly how that translates to the United States, but think about it next time you’re looking at a menu or plotting out the week’s dinners, if the warm glow of your awesomely shrinking ecological footprint isn’t enough.

Recipe: Black Beans and Rice

Sometimes “recipe” is putting a little strongly. These are the foods that are basic concepts as much as they are dishes. The PB&J leaps to mind, (one of the reasons it makes a great mascot for the PB&J Campaign) but much more of the world subsists on the low-on-the-food-chain classic pairing of beans and rice.

Red beans and rice, black beans and rice, rice and dahl, Hoppin’ John, basically any beans go well with rice, either as two distinct dishes eaten together or cooked together as in this great black beans and rice recipe from the NYTimes’ Recipes for Health series. (I would use more beans relative to rice, and I think it’s okay if you use canned beans) – in almost any case, eating rice and beans for lunch or dinner (I suppose breakfast too) will help shrink your carbon footprint, use less water, cut your embodied pollution, and use less land than the animal produce alternatives.

We spend a lot of time on beans, but what about that rice? When Americans think ‘rice’ we usually think white rice, but we should really be thinking more about brown. White rice is brown rice that has had almost all of its fiber, protein, and a lot of its vitamins and minerals stripped away, leaving a little nugget of starch. Brown rice, by that token, is a whole lot better for you – a complex carbohydrate instead of the simple. Check out this Well Blog post to learn about an interesting study linking brown rice consumption to lower diabetes risk. It takes longer to cook, although a pressure cooker will cut the cooking time back down to under twenty minutes (that pressure cooker will help with beans too).

PB&J vs. the Hot Dog

The PB&J Campaign is all about how we can make a big difference (cutting greenhouse gas emissions and other pollution, conserving water, using less land) one meal at a time by eating a plant-based meal such as a PB&J (or falafel, veg chili, etc.). Each meal is an opportunity, but one can make a difference and not swear off favorite animal products. Maybe stick with the ice cream for summer desserts or the brisket or roasted chicken on Friday night, but the PB&J might be a fine substitute for a bologna sandwich or a hot dog.

Now it turns out that the bologna or the hot dog are exactly what you should replace. Tara Parker-Pope of the New York Times’ Well Blog commented on a recent meta-analysis that indicates that processed meats, such as lunch meat, sausages and hot dogs, and bacon, are associated with more heart disease and diabetes (the study did not look at links to other illnesses, such as colon cancer, as the Well post noted), but that unprocessed meats don’t seem to be associated with increased incidence of heart disease and diabetes.

Of course Parker-Pope notes that cutting back on unprocessed meat can help the environment (and we appreciate the link to the PB&J Campaign), and we invite you to check out our explanation of how this works, but, as you’re looking to improve your health as you improve the planet’s health, start with the bacon.

One last little request – we invite you to write letters to your editors pointing out that eating more plant-based meals instead of the processed meat can help us shrink our footprints (water, carbon, land) just as we’re reducing our risk of heart disease and diabetes. Sometimes we underestimate how closely media outlets pay attention to our feedback, but it’s a great way to get some stories run and to raise the profile of the PB&J Campaign and of the overall topic of the impact of eating lower on the food chain.

More PB&Js = Less Toxic?

Although the PB&J Campaign is an environmental project, showing people how they can help the environment (reducing their carbon footprints, cutting water use and pollution, conserving land) by eating more plant-based meals like the PB&J, sometimes it’s hard to pass up a fun, related health story.

And what’s not fun about toxic chemicals and overuse of antibiotics…, or rather eating less toxic chemicals and incidental antibiotics? A recently published Korean study looked at blood levels of antibiotics and some widely-prevalent, hormone-disrupting chemicals to get a sense of how much of the levels common in people come from meat. The way it worked is that they tested the levels of these chemicals in the research subjects before and then at the end of religious retreats to Buddhist temples, where they’d be eating a vegetarian diet. At the end of the retreats the people had way lower levels in their blood.

Now it’s worth mentioning some vague points in the study – they didn’t define what “vegetarian” meant, so they might still have been eating dairy products, and the temples might also have prepared food using techniques or equipment less likely to pass on some of those hormone disruptors. Still, given that the antibiotics levels seemed linked to animal product consumption prior to the retreat (all the subjects had been off medical antibiotics prior to the retreat), there seems to be a strong connection there, at least. Check out this nice analysis from Environmental Health for more discussion.

What’s the PB&J Campaign angle? Well, it sure looks like making a diet more plant-based can reduce the levels of some nasty chemicals in our bodies, while you’re helping save the planet, of course. Eating organic (and thus more expensive) animal products could probably help too, and another way of looking at it is that eating more PB&Js (or bean burritos, tofu, etc.) is a nice way to be able to afford to buy higher-quality, less toxic animal products by cutting back overall.