Tag Archive for: phytonutrient

Nutrition Research: Incomplete

/in /by

In July and August, I wrote about recently published studies on multivitamins and mortality and fish oil and atrial fibrillation. My criticism of those observational studies was because the analyses of the data were incomplete, in my opinion. Here’s how the study we just finished on quercetin and irritable bowel did the correct analysis.

Researchers focused on the subjects with an irritable bowel condition and examined a single nutrient. They already knew that increased fruit and vegetable intake benefitted people with irritable bowels; they specifically examined the quercetin content of those vegetables and fruit to see if subjects who ate those foods needed fewer enterotomies and had lower mortality. They did. This is the way nutrition research should be done.

That’s exactly what they did not do in the multivitamin and fish oil studies. It isn’t like they didn’t have the data; one of the studies used the exact same database of subjects with the nutrition data already collected. They could have analyzed by nutrient, whether it was a macronutrient such as protein, carbohydrate, and fat; by the source of the protein, fat, and carbohydrate intake; or by specific nutrients such as calcium, beta-carotene, or type of fish oil. I could go on, but the point is they could have done more. But as I suggested, when physicians and statisticians are the only experts used—without nutritionists and dieticians—they apparently didn’t know the correct questions to ask.

As a result, we’re now stuck with physicians and other healthcare professionals questioning the use of multivitamins and fish oil. Experience tells me that will be hanging over our heads for years.

During the conclusion and recommendation section of every study, they always finish the observational studies with something like “This study doesn’t provide cause and effect; we need randomized controlled trials to test these findings.” I submit we need more thoughtful analysis of the data used in these studies. The way I see it, those studies were disasters, and there are more to come in the near future. Next week we’ll look at a study that condemns green tea extract and turmeric.

What are you prepared to do today?

        Dr. Chet

Quercetin and Irritable Bowel

/in /by

In the study I talked about on Saturday, the typical way of analyzing this data is to divide the group into segments by a specific variable and then compare the hazard ratios. In this case, the variable was quercetin and they chose to divide the subjects up by quartiles. During the follow-up time of nine years, there were 193 enterotomy events and 176 deaths. Compared with participants in the lowest quartile, those with irritable digestive conditions in the highest quartiles of quercetin intake were associated with a 54% lower risk of enterotomy and 47% decrease in all-cause mortality. In simpler terms, it cut the risk of a serious outcome by half. The relationship was the same regardless of the type of irritable bowel condition for both enterotomy and all-cause mortality with the exception of mortality of ulcerative colitis.

What does all this mean? There’s some type of positive relationship for people with serious digestive disorders who eat plant foods that contain quercetin. While interesting, this type of study doesn’t provide cause and effect—just a positive relationship. Stated simply, as people increase their quercetin-containing plant intake, the risk of having issues with serious outcomes from digestive disorders decreases. Quite correctly, the researchers recommend further research in clinical trials before the results can be confirmed.

The message: eat your vegetables and fruit. Here is a list of the top five vegetables and fruits containing quercetin. For vegetables:

  • Hot peppers (but please, no Carolina Reaper or anything that strong)
  • Broccoli and other cruciferous vegetables
  • Red onions
  • Herbs such as dill and cilantro
  • Capers

For fruit:

  • Apples
  • Tomatoes
  • Dark-skinned grapes
  • Green tea
  • Red wine if you drink alcohol

Maybe there is something to the old saying “an apple a day, keeps the doctor away.” If it keeps the heartburn away, that would do it for me.

You may think we’re done. Remember that Memo on making a single decision that has a long-term impact? I’ll tie that and this study together on Saturday.

What are you prepared to do today?

        Dr. Chet

Reference:  The Journal of Nutrition. 2024;154(6):1861-1868

If You Have an Irritable Bowel…

/in /by

It seems many people experience digestive issues, from constipation, heartburn, and many types of irritation in their bowels. Many people are avoiding some food or ingredient—from gluten, most often found in wheat and bread products, to certain ingredients that are found in food, at least the foods that are available today. I have a slight hiatal hernia, a tear in the lining between my stomach and my lungs, and that can cause reflux; eat too much and I pay the price. Based on a recently published study, those of us who have any type of irritated digestive system just might find the answer in the produce section of our markets.

Researchers used the UK BioBank database to find subjects who had completed five of the 24-hour dietary recalls in a follow-up period of nine years. With that criterion met, subjects were recruited through electronic medical records as having conditions related to the digestive system under the umbrella term total irritable bowel. The researchers used the dietary history to identify all the foods the subjects ate that contained the phytonutrient quercetin; prior research had shown that the consumption of fruits and vegetables with that nutrient showed some benefit for people with digestive issues. The researchers wanted to confirm or refute those observations.

The researchers were able to identify 2,293 participants with serious digestive issues in the database. Diet information was collected using 24-hour dietary recalls; the researchers determined quercetin intake based on nutrient databases that estimated the amounts in the foods consumed.

The researchers were interested in two specific outcomes: enterotomy (the surgical opening of the digestive system to repair damage) and all-cause mortality. The researchers analyzed the data to estimate hazard ratios: the probability that someone will experience those outcomes over the follow-up time, which again, was over nine years. What did they find? I’ll let you know on Tuesday.

What are you prepared to do today?

        Dr. Chet

Reference: The Journal of Nutrition. 2024;154(6):1861-1868

Flavonols: Eat, Drink, and Maybe Live Longer

/in /by

The analyses of the NHANES study on flavonols and mortality did more than just look at a class of phytonutrients; researchers also looked at the individual flavonols and how they impacted mortality. A little background first.

Flavonoids

Flavonoids are a group of phytonutrients made up of six classes of nutrients. They are flavan-3-ols, flavones, flavanones, anthocyanidins, and the previously mentioned flavonols. Each of those classes are made up of individual phytonutrients. Flavonols have four primary phytonutrients in its class: quercetin, kaempferol, myricetin, and isorhamnetin. We’ll skip the rest of the individual phytonutrients in the other classes because they weren’t part of the study.

The researchers examined the reduction in mortality for each flavonol phytonutrient. When comparing the first quartile (lowest) with the fourth quartile (highest) intake, not every phytonutrient reduced the mortality from all conditions. In other words, the overall reduction in mortality was greatest when looking at total flavonol intake, not in any single phytonutrient. Too often research focuses on single phytonutrients as potential treatments of conditions and diseases, so it’s great to see a study that looks at total intake of a class of nutrients.

Absorption

As mentioned, flavonols are one part of the flavonoids. One characteristic is that they seem to be poorly absorbed. Or are they? It could be that there are unknown genetic factors that impact absorption and/or utilization of those nutrients. It may be that when isolated from a plant, the absorption is interfered with in some way that’s not apparent. It may be that the microbiome has a role to play in absorption.

What is most likely is that when eaten or drunk in its natural or prepared state, it is the interaction of all the flavonols that help absorption. Or it may be the combinations of flavonoids found in specific foods that work together for absorption.

What foods have the highest flavonol content? When looking at mg/100 grams, raw onions, cooked onions, apples with the peel, brewed black decaf tea, and brewed black tea top the list. When looking at the top three consumed? Onions, black tea, and apples top the list, but beer comes in fourth place. While the amount per 100 grams is low, we consume a lot of it.

The Bottom Line

At the end of the day, the most important thing to know is that we have to consume flavonols to get the benefits. In reality, your mama was right: eat your fruits and vegetables. They’re good for you. And if you chase them down with a beer, that’s probably okay as well.

What are you prepared to do today?

        Dr. Chet

Reference: Nature Reports. 2024. https://doi.org/10.1038/s41598-024-55145-y2. Arch

Fiber: Food or Supplements?

/in /by

We don’t seem to eat enough whole or minimally processed plant foods, so the researchers were trying to discover whether getting fiber, especially insoluble fiber, was better from plant material or whether taking fiber in supplement form would suffice.

Researchers approached the question from the perspective of other beneficial nutrients that might be found in plants that might be processed out of fiber supplements. They conducted a literature search and found that just 44 studies that examined the phytonutrient content of many plant foods and met their criteria. They focused on insoluble fiber which would be found in the skin of apples and beans, seeds and nuts, and many other components of raw foods that are discarded in processing.

Bioactive Nutrients are Present

While the techniques are complicated and resulted in very long lists of various phytonutrients, insoluble fiber contains many of them. Part of the issue is that there are components we would never eat such as corn cobs or the peels of oranges. Fortunately, there are enough plants that we ordinarily eat that contain insoluble fiber.

That doesn’t mean that soluble fiber such as inulin and psyllium are not beneficial; they add bulk to the stool and help the digestive system in general. It also doesn’t mean that every source of insoluble fiber is beneficial; phytic acid found in the shells of beans can prevent minerals from being chelated and thus absorbed, but cooking the beans breaks down phytic acid without destroying the insoluble fiber. The good news is that the phytonutrients are there as we eat the foods.

Food or Supplements?

The study didn’t completely answer the question, mostly because of the paucity of research on insoluble fiber (or any type of fiber) and the beneficial nutrients it contains. They suggested that the challenges presented to the taste and textures of adding insoluble fiber to foods might be too challenging to be accepted by the public. While it’s easy to say “eat more plant-based foods,” getting people to do it is really difficult.

So if “Food or supplements?” is the question, my answer would be “Yes!” I think the convenience of having psyllium and inulin in powders is great because they mix well with water and can be put into drinks as long as they are consumed quickly. Adding a squeeze of lemon or a no-calorie flavor packet can make the drink more palatable.

For insoluble fiber, I think food is the way to go. Apples and pears with their peels, cooked red, black, chickpea, great northern, and other beans, root vegetables such as sweet potatoes and yams, carrots, oatmeal, flax seed, and bran as in bran flakes are excellent choices. They can be used in cooking, so be creative. Black bean salad, hummus, chili with beans, and many more sources can be eaten on a regular basis. We just have to seek them out.

The Bottom Line

The big benefit of insoluble fiber from foods is all the other phytonutrients you’ll also be getting. Just make sure you use spices to make them more palatable, including a little sugar if necessary. With Thanksgiving less than a week away, think of the sides you can create that could include root vegetables, beans, and other foods high in insoluble fiber. The old saying about an apple a day was more correct than we knew.

Speaking of Thanksgiving, Paula, Riley, Jamie, and I wish you all a Happy Thanksgiving. I hope you get to spend it with family and friends. The Memo will resume the following week. Be well and travel safely.

What are you prepared to do today?

        Dr. Chet

Reference: Nutrients 2023, 15, 4138. https://doi.org/10.3390/nu151941382.

Side 2: Why Powders Are Better than Plants

/in /by

You might have thought that I was a food-only proponent when it comes to nutrition. Not in the least—I’m a big fan of the right kinds of supplements. I think we should start with real food, but we also have to acknowledge that the average person’s plant intake is woefully low: one or two servings per day of vegetables and two or three servings of fruit. It’s even less if we deduct juices. There are many reasons for that lack, but we need a practical solution. Powders can provide a partial answer, whether mixed into smoothies or plain water or consumed as capsules.

The primary reason vegetable and fruit powders are better is consistent content. If the label says 500 mg of blueberry concentrate or 300 mg of acerola cherry concentrate, that content should be there scoop to scoop or capsule to capsule. The produce we buy or even raise ourselves can vary widely in phytonutrient content.

Second, for the most part, the powders are convenient. If you always have a smoothie for breakfast, a scoop or two of the vegetable and fruit powder is a quick way to improve your diet.

The Issue with Powders

The phytonutrient content per scoop or capsule may change depending on when the vegetable or fruit was harvested—even in as little as a couple of hours. It doesn’t mean they won’t be there, only that the types and quantities of phytonutrients may vary slightly.

Another issue is finding a reliable, high-quality manufacturer. This may be a great time to listen to “The Characteristics of a Quality Manufacturer” in my audio on Supplementing Your Diet. If you don’t have a copy, the MP3 is only $4.95 and you be listening in a couple of minutes.

The Bottom Line

There’s room in a healthy diet to get your eight to ten servings of vegetables and fruits from food with an assist from vegetable and fruit powders if you need them. There are small issues with each approach, but using a complementary approach may help you achieve your nutritional goals while giving you the flexibility to meet your nutritional needs even with a demanding, unpredictable schedule. The lesson: Eat better. Some plants plus some powders can give you the best of both worlds, and that can help you get closer to the nutrients your body needs.

What are you prepared to do today?

        Dr. Chet

Side 1: Why Plants Are Better than Powders

/in /by

A month ago I addressed the increased interest in getting vegetables and fruits from powders; now let’s get into more detail.

First, eating vegetables and fruits automatically increases our fluid intake. The exact water content of different plants varies, but the average plant is about 90% water by weight. The water is somewhat purified by the root system; it’s not the equivalent of a water treatment system, but it’s something.

Second, the fiber content of the plants contributes to the 25 to 30 grams of fiber we need every day. The fiber can also add to the prebiotic needed to feed the probiotics. Depending on the way the plants are prepared, they may also contain probiotics.

Those are substances you don’t get in powders unless they’re specifically added or not removed. Are foods always better? No, but they’re the perfect delivery system providing we eat them every day.

But there are two sides to every issue. On Saturday, we’ll talk about how powders are better than foods.

What are you prepared to do today?

        Dr. Chet

Do You Need a Fruit-and-Vegetable Concentrate?

/in /by

Vegetable-concentrate and fruit-concentrate products are popular now, judging by the number of ads on TV and the web; the implication is that they can replace real fruits and vegetables in the diet.

For the fruit concentrate, manufacturers remove all the fiber and water, yielding concentrates from various fruits and phytonutrient blends plus aloe vera. The supplements include 2,000 mg per serving with 17 ingredients; that works out to 120 mg per ingredient if equally divided. Are those amounts significant, especially after removing the fiber and water? Hard to say without a lot of research on each nutrient to find the effective amount, both individually and combined; for example, we don’t know if there’s an interaction between the nutrients that affects absorption and utilization.

One more type of concentrate would be single-nutrient supplements, such as a specific type of curcuminoids from a certain species of turmeric. Manufacturing is not my area; it takes some hard-core chemistry to figure out how to get the nutrient you want.

Here’s an example: curcumin is extracted from the dried root of the rhizome Curcuma longa. After drying, the process of extraction requires the raw material to be ground into powder and washed with a solvent that selectively extracts coloring matter, the curcuminoids, which then can be put into supplement form. Might there be some vitamins and minerals remaining? Probably, but that isn’t the point of the supplement. The curcuminoids are.

The Bottom Line

At the end of the day, our bodies need the fiber and water from plants to feed our microbiome. That’s why these types of products complement the vegetables and fruits you’re supposed to be eating—they don’t replace them.

I think the best way to get the best of both worlds is eating the five to ten servings of fruits and vegetables you’re supposed to eat, plus taking a multivitamin-multimineral with plant concentrates as insurance to make sure you get all the basic nutrients. If you know you’re not going to be eating as you should for a while, like an accountant working 14-hour days at tax time or a student cramming for finals, a fruit-and-vegetable concentrate might be a good addition. Then add specific concentrate-phytonutrient blends you may be missing in your diet; for example, if you hate mushrooms, take a mushroom-blend supplement. Now you’ve got all your bases covered.

What are you prepared to do today?

        Dr. Chet

Reference: www.fao.org/fileadmin/templates/agns/pdf/jecfa/cta/61/Curcumin.pdf

Vitamins and Minerals in Supplements

/in /by

I got an interesting question last week about a supplement that contained a blend of fruit and vegetable concentrates: vitamins and minerals aren’t included on the label, so are they in there? The answer is probably. It all comes down to the purpose of the supplement.

A concentrate is typically the entire vegetable or fruit with the water removed by a dehydration process; whatever is in the plant will be in the concentrate. You could liken this to drying a fresh herb to use as a spice. A more sophisticated process is to remove some of the fiber as well; that would remove solids, but some vitamins and minerals could remain.

Another variation is if a company were to focus on a phytonutrient blend, such as the polyphenols and hesperidin from citrus fruit. They would standardize the supplement to the amounts of those phytonutrients but wouldn’t be concerned about vitamins or minerals unless they met a percentage of the RDA.

There is still more precision in concentrate and phytonutrient supplements, and we’ll talk about them on Saturday.

What are you prepared to do today?

        Dr. Chet

Phytonutrients: Diet or Supplements?

/in /by

The study that we looked at this week demonstrated that flavonoid intake is related to socioeconomic status. It also demonstrated that most of that difference comes from the consumption of tea. All well and good.

What stood out to me was the lack of phytonutrient intake. While there were some small differences in the other flavonoids besides flavan-3-ols, the total intake of flavonoids was low. Even though we’re talking about just one class of phytonutrients, the total flavonoid intake minus the flavonoids from tea was about 140 milligrams per day. That’s reflective of a poor diet that does not include as many sources of phytonutrients as it should: not enough vegetables, fruit, beans, nuts, and others. And it hasn’t changed in the six years of the study. Most people still don’t eat enough plant-based foods to do themselves any good.

Supplements: An Insurance Plan

The study demonstrated the need for the regular use of supplements containing plant concentrates. A plant concentrate is the plant or its fruit or its root or its leaves, minus the water and the fiber. It should also have been harvested at the peak of nutrition, not the peak of flavor and taste. The plant concentrates contain all the phytonutrients that are contained within the plant, and that includes not only the flavonoids that were the subject of this study, but all of the other types of phytonutrients that we need on a regular basis.

The plant concentrates may be found in multivitamin-minerals, as part of a fruit-and-vegetable concentration, or maybe even as a stand-alone. We’re not talking about treating diseases with these supplements; we’re talking about getting the nutrition that you’re supposed to be getting from the foods that you eat (but you’re not). To me, this study pretty much proves that everyone needs to take supplements with plant concentrates every day. They provide good backup while you work on improving your diet.

The Bottom Line

If you want the best chance at preventing degenerative diseases, you need optimal nutrition. That starts with what you eat, including all those phytonutrient-containing vegetables, fruits, beans, grains, and aromatic herbs used to season your food. As a backup, take supplements that contain plant concentrates to complement your diet. It’s not either/or; it’s using them both to get to better health.

Paula and I will be taking some time off to work on more jobs around the house. We’ll be back after a short break.

What are you prepared to do today?

        Dr. Chet

Reference: J Nutr 2020;150:2147–2155.