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:


The Benefits of Wakame Seaweed Salad on Blood Pressure

I used to think of seaweed as just a beneficial whole-food source of minerals like iodine, for which it is the most concentrated dietary source. Indeed, just a daily half-teaspoon of mild seaweeds, like arame or dulse, or two sheets of nori should net you all the iodine you need for the day. But, the intake of seaweeds is advised not only as a whole-food source of iodine, but also, evidently, “for the prevention of lifestyle-related diseases, including cancer, cardiovascular and cerebrovascular disease….” Based on what?

As I discuss in my video Wakame Seaweed Salad May Lower Blood Pressure, the reasoning is that the Japanese live long and eat seaweed, so there is speculation that seaweed might have “influence on life expectancy,” based on suggestive reports. But when we see long lists of the supposed benefits a particular food is purported to have, such as “compounds found in [seaweed] have various biological activities including anticoagulant, anti-viral, antioxidant, anti-allergic, anti-cancer, anti-inflammatory, anti-obesity, and neuroprotective properties,” we need to know if they are based on clinical data, meaning studies with actual people, or so-called preclinical data, that is, from test tubes and lab animals. I mean, what are we supposed to do with a study talking about the effects of “seaweed-restructured pork diets” on rats? Those researchers tried to use seaweed, as well as other ingredients, to “improv[e] the ‘image’ of meat product.” Researchers also tried to add grape seeds to meat, they tried flaxseeds, they tried walnuts, they tried purple rice, and they even tried “thong-weed.”

When you look at epidemiological studies, where you compare the diets and disease rates within a population, you see that Japanese pre-schoolers who eat seaweed tend to have lower blood pressures, suggesting “seaweed might have beneficial effects on blood pressure among children.” That could make sense given all the minerals and fiber in seaweed, but cause and effect can’t be proven with this kind of study. Perhaps other components of the diet that went along with seaweed eating that made the difference.

It’s even harder to do these kinds of studies on adults, since so many people are on high blood pressure medications. University of Tokyo researchers took an innovative approach by comparing the diets of people on different intensities of medication: low-dose of a single blood pressure drug, high-dose of a single drug, and multiple drugs. And, although they all had artificially normalized blood pressure “as a result of effective medication,” those who ate the most fruits and sea vegetables tended to be the ones on the lower dose of a single drug, supporting a dietary role for seaweed. An interesting finding, but why not just put it to the test?

A double-blind, crossover trial found that seaweed fiber lowered blood pressure, apparently by pulling sodium out of the system. Real seaweed couldn’t be used in the study, because the subjects wouldn’t be able to be fooled with a placebo, but why not just put whole powdered seaweed into pills? That was finally attempted ten years later. Compared to doing nothing, subjects receiving a daily dose of dried wakame powder in capsules had beautiful drops in blood pressure. The researchers, however, desalinized the seaweed, taking out about two-thirds of the sodium naturally found in it. So, we still don’t know if eating seaweed salad is actually going to help with blood pressure. What we need is a randomized, controlled trial with plain, straight seaweed. No one had ever done that research, until…they did!

Six grams of wakame, with all of its natural sodium, led to a significant drop in blood pressure, especially in those who started out with high pressure. The subjects experienced only minor side effects and ones that could be expected with increasing fiber intake. A nice thing about whole-food, plant-based interventions is that we sometimes get good side effects, such as the resolution of gastritis (stomach inflammation) some subject had been having, as well as the disappearance of chronic headaches. 

What other foods might help with high blood pressure? See:

For more on preventing and treating hypertension, one of our leading killers, see:

Want more on seaweed and iodine? Check out:

My video Salt of the Earth: Sodium and Plant-Based Diets further addresses the sodium question.

In health,
Michael Greger, M.D.

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

How to Increase Gut Bacterial Richness

We live in an “obesogenic environment,” with cheap junk food everywhere, thanks in part to subsidies going to the “‘food industrial complex,’ which manufactures obesogenic foods that foster addiction…The root causes…[may] make obesity difficult to escape,” but a lot of people do. If it were simply the external environment, why isn’t everyone obese?

“Some individuals seem to be more susceptible to the obesogenic environment…than others,” which suggests a genetic component, supported by studies of twins and adopted kids, but the genes that have been identified so far account for only 6 to 11 percent of the genetic variation in body mass index between individuals. Perhaps variation in our “other genome”—that is, all the different microbes that inhabit our body, known as the microbiome—may be playing a role. We have a hundred times more bacterial genes inside us than human genes.

As I discuss in my video Gut Microbiome: Strike It Rich with Whole Grains, a study found that people tend to fall into one of two groups: those who have lots of different types of bacteria in their gut (high “gut bacterial richness”) and those with relatively few types. Those with low bacterial richness had more overall body fat, insulin resistance, which is the cause of type 2 diabetes, high triglycerides, and higher levels of inflammatory markers, like C-reactive protein, compared to those with high bacterial richness. Not only did people with lower bacterial richness start out heavier, but the obese individuals with lower bacterial richness also gained more weight over time.

The question then becomes: Can a dietary intervention have any impact “A number of studies have associated increased microbial richness…with diets higher in fruits, vegetables, and fiber.”

Just giving fiber-type supplements doesn’t seem to boost richness, however, but the “compositional complexity” of a whole food, like whole grains, “could potentially support a wider scope of bacterial taxa,” types of bacteria, “thereby leading to an increase in diversity.” Human studies to investigate the effects of whole grains had been neglected, though…until now.

Subjects were given whole-grain barley, brown rice, or a mixture of both for a month, and all three caused an increase in bacterial community diversity. Therefore, it may take a broad range of substrates to increase bacterial diversity, and this can be achieved by eating whole plant foods.

Moreover, the alterations of gut bacteria in the study coincided with a drop in systemic inflammation in the body. We used to think that the way fiber in whole grains helped us was by gelling in our small intestine right off of our stomach, slowing the rate at which sugars were absorbed and blunting the spike in blood sugars one might get from refined carbs. We now know, however, that fiber is broken down in our colon by our friendly flora, which release all sorts of beneficial substances into our bloodstream that can have anti-inflammatory effects, as well. So, perhaps what’s happening in our large intestine helps explain the protective effects of whole grain foods against type 2 diabetes.

Interestingly, the combination of both barley and brown rice worked better than either grain alone, suggesting a synergistic effect. This may help explain “the discrepancy of the health effects of whole grains obtained in epidemiological [population-based] and interventional studies.”

Observational studies “strongly suggest” that those who consume three or more servings of whole grains a day tend to have a lower body mass index, less belly fat, and less tendency to gain weight, but recent clinical trials, where researchers randomized subjects to eat white bread rolls versus whole-wheat rolls, failed to provide evidence of a beneficial effect on body weight. Of course, whole grains are so superior nutritionally that they should continue to be encouraged. However, the “[i]nterventional trials might have failed to show [weight] benefits because they focused on a limited selection of whole grains, while in epidemiological trials [or the population studies], subjects are likely to consume a diverse set of whole grains which might have synergistic activities.”

Until recently, we knew very little about how powerfully our gut bacteria can affect our health. Catch up on the latest science with these related videos:

When it comes to rice, even white rice can be better than many choices, but brown rice is better and pigmented rice is probably the best. See my videos Kempner Rice Diet: Whipping Us Into Shape and Is It Worth Switching from White Rice to Brown? for more.

But what about the arsenic in rice? Learn more:

In health,
Michael Greger, M.D.

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