The Crowding Out Strategy to Eating Healthier

It may be more expedient politically to promote an increase in consumption of healthy items rather than a decrease in consumption of unhealthy items, but it may be far less effective.

The World Health Organization has estimated that more than a million deaths “worldwide are linked to low fruit and vegetable consumption.” What can be done about it? I explore this in my video Is it Better to Advise More Plants or Less Junk?

There’s always appealing to vanity. A daily smoothie can give you a golden glow as well as a rosy glow, both of which have been shown to “enhance healthy appearance” in Caucasian, Asian, and African skin tones, as you can see at 0:24 in my video.

What about giving it away for free?

A free school fruit scheme was introduced in Norway for grades 1 through 10. Fruit consumption is so powerfully beneficial that if kids ate only an additional 2.5 grams of fruit a day, the program would pay for itself in terms of saving the country money. How much is 2.5 grams? The weight of half of a single grape. However, that cost-benefit analysis assumed this minuscule increased fruit consumption would be retained through life. It certainly seemed to work while the program was going on, with a large increase in pupils eating fruit, but what about a year after the free fruit program ended? The students were still eating more fruit. They were hooked! Three years later? Same thing. Three years after they had stopped getting free fruit, they were still eating about a third of a serving more, which, if sustained, is considerably more than necessary for the program to pay for itself.

There were also some happy side effects, including a positive spillover effect where not only the kids were eating more fruit, but their parents started eating more, too. And, although the “intention of these programs was not to reduce unhealthy snack intakes,” that’s exactly what appeared to happen: The fruit replaced some of the junk. Increasing healthy choices to crowd out the unhealthy ones may be more effective than just telling kids not to eat junk, which could actually backfire. Indeed, when you tell kids not to eat something, they may start to want it even more, as you can see at 2:20 in my video.

Which do you think worked better? Telling families to increase plants or decrease junk? Families were randomly assigned to one of two groups, either receiving encouragement to get at least two servings of fruits and veggies a day, with no mention of decreasing junk, or being encouraged to get their junk food intake to less than ten servings a week, with no mention of eating more fruits and veggies. What do you think happened? The Increase Fruit and Vegetable intervention just naturally “reduced high-fat/high-sugar intake,” whereas those in the Decrease Fat and Sugar group cut back on junk but didn’t magically start eating more fruits and vegetables.

This crowding out effect may not work on adults, though. As you can see at 3:12 in my video, in a cross-section of over a thousand adults in Los Angeles and Louisiana, those who ate five or more servings of fruits and veggies a day did not consume significantly less alcohol, soda, candy, cookies, or chips. “This finding suggests that unless the excessive consumption of salty snacks, cookies, candy, and sugar-sweetened beverages”—that is, junk—“is curtailed, other interventions…[may] have a limited impact….It may be politically more expedient to promote an increase in consumption of healthy items rather than a decrease in consumption of unhealthy items, but it may be far less effective.” In most public health campaigns, “messages have been direct and explicit: don’t smoke, don’t drink, and don’t take drugs.” In contrast, food campaigns have focused on eat healthy foods rather than cut out the crap. “Explicit messages against soda and low-nutrient [junk] foods are rare.”

In the United States, “if one-half of the U.S. population were to increase fruit and vegetable consumption by one serving each per day, an estimated 20,000 cancer cases might be avoided each year.” That’s 20,000 people who would not have gotten cancer had they been eating their fruits and veggies. The U.S. Department of Agriculture recommends we “fill half [our] plate with colorful fruits and vegetables,” but less than 10 percent of Americans hit the recommended daily target. Given this sorry state of affairs, should we even bother telling people to strive for “5 a day,” or might just saying “get one more serving than you usually do” end up working better? Researchers thought that “the more realistic ‘just 1 more’ goal would be more effective than the very ambitious ‘5 a day’ goal,” but they were wrong.

As you can see at 4:56 in my video, those told to eat one more a day for a week, ate about one more a day for a week, and those told to eat five a day for a week did just that, eating five a day for a week. But here’s the critical piece: One week after the experiment was over, the group who had been told to eat “5 a day” was still eating about a serving more, whereas the “just 1 more” group went back to their miserable baseline. So, more ambitious eating goals may be more motivating. Perhaps this is why “in the US ‘5 a day’ was replaced by the ‘Fruits and Veggies—More Matters’ campaign…in which a daily consumption of 7–13 servings of fruits and vegetables – FVs –  is recommended.” However, if the recommendation is too challenging, people may just give up. So, instead of just sticking with the science, policy makers evidently need to ask themselves questions like “How many servings are regarded as threatening?”


For more on appealing to vanity to improve fruit and vegetable consumption, see my videos Eating Better to Look Better and Beauty Is More Than Skin Deep.

What does the science say about smoothies? See:

The flipside of free fruit programs is to tax instead of subsidize. Learn more by checking out my video Would Taxing Unhealthy Foods Improve Public Health?

For more on the paternalistic attitude that you don’t care enough about your health to be told the truth, see my videos Everything in Moderation? Even Heart Disease? and Optimal Diet: Just Give It to Me Straight, Doc.

I explore this same patronizing attitude when it comes to physical activity in How Much Should You Exercise?

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

 

What Happens if You Have Red Wine or Avocados with a Meal?

Whole plant sources of sugar and fat can ameliorate some of the postprandial (after meal) inflammation caused by the consumption of refined carbohydrates and meat.

Studies have shown how adding even steamed skinless chicken breast can exacerbate the insulin spike from white rice, but fish may be worse. At 0:18 in my video The Effects of Avocados and Red Wine on Meal-Induced Inflammation, you can see how the insulin scores of a low-carbohydrate plant food, peanuts, is lower compared to common low-carb animal foods—eggs, cheese, and beef. Fish was even worse, with an insulin score closer to doughnut territory.

At 0:36 in my video, you can see the insulin spike when people are fed mashed white potatoes. What do you think happens when they’re also given tuna fish? Twice the insulin spike. The same is seen with white flour spaghetti versus white flour spaghetti with meat. The addition of animal protein may make the pancreas work twice as hard.

You can do it with straight sugar water, too. If you perform a glucose challenge to test for diabetes, drinking a certain amount of sugar, at 1:10 in my video, you can see the kind of spike in insulin you get. But, if you take in the exact same amount of sugar but with some meat added, you get a higher spike. And, as you can see at 1:25 in my video, the more meat you add, the worse it gets. Just adding a little meat to carbs doesn’t seem to do much, but once you get up to around a third of a chicken’s breast worth, you can elicit a significantly increased surge of insulin.

So, a chicken sandwich may aggravate the metabolic harm of the refined carb white bread it’s on, but what about a PB&J? At 1:49 in my video, you can see that adding nuts to Wonder Bread actually calms the insulin and blood sugar response. What if, instead of nuts, you smeared on an all fruit strawberry jam? Berries, which have even more antioxidants than nuts, can squelch the oxidation of cholesterol in response to a typical American breakfast and even reduce the amount of fat in your blood after the meal. And, with less oxidation, there is less inflammation when berries are added to a meal.

So, a whole plant food source of sugar can decrease inflammation in response to an “inflammatory stressor” meal, but what about a whole plant food source of fat? As you can see at 2:38 in my video, within hours of eating a burger topped with half an avocado, the level of an inflammatory biomarker goes up in your blood, but not as high as eating the burger without the avocado. This may be because all whole plant foods contain antioxidants, which decrease inflammation, and also contain fiber, which is one reason even high fat whole plant foods like nuts can lower cholesterol. And, the same could be said for avocados. At 3:12 in my video, you can see avocado causing a significant drop in cholesterol levels, especially in those with high cholesterol, with even a drop in triglycerides.

If eating berries with a meal decreases inflammation, what about drinking berries? Sipping wine with your white bread significantly blunts the blood sugar spike from the bread, but the alcohol increases the fat in the blood by about the same amount. As you can see at 3:40 in my video, you’ll get a triglycerides bump when you eat some cheese and crackers, but if you sip some wine with the same snack, triglycerides shoot through the roof. How do we know it was the alcohol? Because if you use dealcoholized red wine, the same wine but with the alcohol removed, you don’t get the same reaction. This has been shown in about a half dozen other studies, along with an increase in inflammatory markers. So, the dealcoholized red wine helps in some ways but not others.

A similar paradoxical effect was found with exercise. If people cycle at high intensity for about an hour a half-day before drinking a milkshake, the triglycerides response is less than without the prior exercise, yet the inflammatory response to the meal appeared worse, as you can see at 4:18 in my video. The bottom line is not to avoid exercise but to avoid milkshakes.

The healthiest approach is a whole food, plant-based diet, but there are “promising pharmacologic approaches to the normalization” of high blood sugars and fat by taking medications. “However, resorting to drug therapy for an epidemic caused by a maladaptive diet is less rational than simply realigning our eating habits with our physiological needs.”

Protein from meat can cause more of an insulin spike than pure table sugar. See the comparisons in my video Paleo Diets May Negate Benefits of Exercise.

Interested in more information on the almond butter study I mentioned? I discuss it further in How to Prevent Blood Sugar and Triglyceride Spikes After Meals.

Berries have their own sugar, so how can eating berries lower the blood sugar spike after a meal? Find out in If Fructose Is Bad, What About Fruit?


For more on avocados, check out:

And here are more videos on red wine:

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

Decreasing Inflammation and Oxidation After Meals

Within hours of eating an unhealthy meal, we can get a spike in inflammation, crippling our artery function, thickening our blood, and causing a fight-or-flight nerve response. Thankfully, there are foods we can eat at every meal to counter this reaction.

Standard American meals rich in processed junk and meat and dairy lead to exaggerated spikes in sugar and fat in the blood, as you can see at 0:13 in my video How to Prevent Blood Sugar and Triglyceride Spikes after Meals. This generates free radicals, and the oxidative stress triggers a biochemical cascade throughout our circulation, damaging proteins in our body, inducing inflammation, crippling our artery function, thickening our blood, and causing a fight-or-flight nerve response. This all happens within just one to four hours after eating a meal. Worried about inflammation within your body? One lousy breakfast could double your C-reactive protein levels before it’s even lunchtime.

Repeat that three times a day, and you can set yourself up for heart disease. You may not even be aware of how bad off you are because your doctor is measuring your blood sugar and fat levels while you’re in a fasting state, typically drawing your blood before you’ve eaten. What happens after a meal may be a stronger predictor of heart attacks and strokes, which makes sense, since this is where most of us live our lives—that is, in a fed state. And it’s not just in diabetics. As you can see at 1:30 in my video, if you follow non diabetic women with heart disease but normal fasting blood sugar, how high their blood sugar spikes after chugging some sugar water appears to determine how fast their arteries continue to clog up, perhaps because the higher the blood sugars spike, the more free radicals are produced.

So, what are some dietary strategies to improve the situation? Thankfully, “improvements in diet exert profound and immediate favorable changes…,” but what kind of improvements? “Specifically, a diet high in minimally processed, high-fiber, plant-based foods such as vegetables and fruits, whole grains, legumes, and nuts,”—antioxidant, anti-inflammatory whole plant foods—“will markedly blunt the post-meal increase” in sugar, fat, and inflammation.

But what if you really wanted to eat some Wonder Bread? As you can see at 2:23 in my video, you’d get a big spike in blood sugar less than an hour after eating it. Would it make a difference if you spread the bread with almond butter? Adding about a third of a cup of almonds to the same amount of Wonder Bread significantly blunts the blood sugar spike.

In that case, would any low-carb food help? Why add almond butter when you can make a bologna sandwich? Well, first of all, plant-based foods have the antioxidants to wipe out any excess free radicals. So, nuts can not only blunt blood sugar spikes, but oxidative damage as well. What’s more, they can even blunt insulin spikes. Indeed, adding nuts to a meal calms both blood sugar levels and insulin levels, as you can see at 3:02 in my video. Now, you’re probably thinking, Well, duh, less sugar means less insulin, but that’s not what happens with low-carb animal foods.

As you can see at 3:23 in my video, if you add steamed skinless chicken breast to your white rice, you get a greater insulin spike than if you had just eaten the white rice alone. So, adding the low-carb plant food made things better, but adding the low-carb animal food made things worse. It’s the same with adding chicken breast to mashed potatoes—a higher insulin spike with the added animal protein. It is also the same with animal fat: Add some butter to a meal, and get a dramatically higher insulin spike from some sugar, as you can see at 3:45 in my video.

If you add butter and cheese to white bread, white potatoes, white spaghetti, or white rice, you can sometimes even double the insulin reaction. If you add half an avocado to a meal, however, instead of worsening, the insulin response improves, as it does with the main whole plant food source of fat: nuts.


I’ve covered the effect adding berries to a meal has on blood sugar responses in If Fructose Is Bad, What About Fruit?, and that raises the question: How Much Fruit Is Too Much?

In addition to the all-fruit jam question, I cover The Effects of Avocados and Red Wine on Postprandial Inflammation.

Vinegar may also help. See Can Vinegar Help with Blood Sugar Control?.

Perhaps this explains part of the longevity benefit to nut consumption, which I discuss in Nuts May Help Prevent Death.

I also talk about that immediate inflammatory reaction to unhealthy food choices in Best Foods to Improve Sexual Function.

Surprised by the chicken and butter reaction? The same thing happens with tuna fish and other meat, as I cover in my video Paleo Diets May Negate Benefits of Exercise.

Also check:

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations: