PAHs Contaminate Supplements?

Written by Dr. Steve Chaney on . Posted in current health articles, Environment and Health, Food and Health, Health Current Events, Supplements and Health

Do Your Supplements Contain Carcinogens?

Author: Dr. Stephen Chaney

 

pahs in supplementsMost of us take supplements to improve our health. We count on those supplements being pure and effective. We don’t expect the supplements we take to contain carcinogenic (cancer causing) contaminants. However, that expectation appears to be unfounded. A recent study found that 72% of supplements tested were contaminated with a particularly dangerous class of cancer causing chemicals called polycyclic aromatic hydrocarbons (PAHs)

Where Do PAHs Come From  andWhy Are TheyDeadly?

Polycyclic aromatic hydrocarbons (PAHs) are produced by incomplete combustion of organic materials. Major environmental sources of PAHs are incomplete burning of gasoline, coal and other fuels. Unfortunately, automobile exhaust, coal burning power plants, and exhaust from factories are almost ubiquitous in today’s world, resulting in significant PAH contamination of our air, water, and soil. The unfortunate truth is that we all live in an increasingly dirty and toxic environment.

pahs can come from highwayAs you might imagine, cigarette smoke is the #1 source of PAHs in humans. However, foods are a major route for PAH exposure in humans as well. There are many food sources of PAHs. For example,

  • Grilling, roasting and frying foods, especially meats, at high temperatures creates PAHs.
  • Smoking fish or meats creates PAHs.
  • Barbecuing meats creates PAHs.
  • Even plant-based foods can contain PAHs if the soil, air or water they were grown in was contaminated.
  • PAHs can be introduced into supplements if any of their ingredients are dried at high temperatures as part of the processing procedure.

By now you are probably realizing that it is not just our environment that is increasingly being contaminated with PAHs. We are all becoming contaminated with PAHs as well. Our bodies are becoming toxic waste dumps.

Unfortunately, PAHs are not innocuous chemicals. Perhaps the best studied and deadliest of the PAHs is a compound called benzo[a]pyrene. It is classified as a class 1 carcinogen and mutagen by the IARC (International Agency for Research on Cancer). Perhaps some explanation is in order:

  • The IARC is an international organization that is charged with evaluating the scientific evidence for the carcinogenicity of various chemicals. It also sets upper limits for safe exposure to those chemicals.
  • Class 1 carcinogens are compounds that the IARC has classified as definitely carcinogenic to humans. Simply put, the IARC considers the scientific evidence to be overwhelming that those compounds are carcinogens.

To date only 118 compounds have been blacklisted by the IARC as class 1 carcinogens and benzo[a]pyrene is one of them. However, many of the other, less studied, PAHs are classified as probable carcinogens by the IARC.

Unfortunately, in most countries of the world (including the United States), PAH limits in food and supplements are unregulated. Because they are unregulated, many supplement companies don’t even test for them. That is unfortunate because a recent study shows that many supplements are contaminated with high levels of PAHs, and their manufacturers didn’t even know it.

Do Your Supplements Contain PAHs or Other Carcinogens?

carcinogens in supplementsThe European Union has taken the lead in regulating PAH levels. They have used the IARC guidelines to create upper allowable limits for PAHs in food and supplements. Separate standards were set for benzo[a]pyrene and the total of the four most common PAH contaminants (benzo[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthrene, and chrysene). Those new regulations just went into effect April 1st 2016.

To gauge the impact of these new regulations on the supplement industry, the EU asked the European Union Reference Laboratory to measure the levels of PAH contamination in supplements sold in the EU prior to the implementation of the new regulations. Because vitamin and mineral supplements are seldom contaminated with PAHs, they were excluded from the study.

The EU Reference Laboratory started collecting a wide range of herbal and botanical supplements, fish and edible oil food supplements, and propolis and other bee supplements sold in the EU in 2013. The Reference Laboratory analyzed 94 different supplements for PAH contamination, and the results of these analyses were published in October 2015 (Z. Zelinkova and T. Wenzyl, Food Additives & Contaminants: Part A, 32: 1914-1926, 2015).

[In case you, like me, were wondering what propolis is, it is a resin like substance that bees use as a glue to hold their hives together. WebMD states that it may have some use as a topical agent for cold sores, genital herpes, and after mouth surgery, but that any other uses are unproven. However, if you visit websites for propolis products you find it in capsules and liquids for internal consumption. You are told that it cures bacterial and fungal infections, cures viral infections like AIDs, cures cancer, and removes warts.]

The results of their analysis were pretty scary:

  • 72% of the supplements tested exceeded EU limits for the four most common PAH contaminants, and 52% exceeded EU limits for benzo[a]pyrene.
  • Propolis and spirulina were the most heavily contaminated supplements. Valerian and St. John’s Wort had moderately high levels of contamination, and some samples of bee pollen, sea buckthorn oil, barley greens, Echinacea, and Ginko far exceeded EU standards.
  • If consumers took the recommended dosage of the two most contaminated products (Premium Spirulina and Propolis Intense) they would more than double their daily intake of PAHs and far exceed what the IARC considers safe.
  • Fish oils generally had low levels of PAH contamination. The authors speculated this may be because fish have the ability to metabolize PAHs. However, other edible oils, particularly sea buckthorn oil and a mixture of garlic oil with soybean and sunflower oils did exhibit significant PAH contamination. The authors speculated that this PAH contamination may have been introduced during the processing of these oils.

Why The PAH and Contamination Problem Is Worse Than You Thought

worseYou might be thinking what could be worse than 72% of supplements being contaminated with cancer causing PAHs? Here is some food for thought.

  • PAHs are just the tip of the iceberg. Many supplements are also contaminated with PCBs and heavy metals. For example:
  • Fish oil is often contaminated PCBs.
  • Rice protein and other rice-derived ingredients are often contaminated with lead and/or mercury.
  • The US regulates PAHs in our water supply, but does not currently regulate PAHs in our supplements. That means that manufacturers that make products primarily for consumption in the US have no incentive to test their products for PAH contamination. Most of them have no idea whether their products are safe or not.
  • There is no guarantee that even products labeled Certified Organic and Non-GMO are free of PAH contamination. For example:
  • Organic certification just means that the crop was raised using organic methods. No analysis of purity is required to assure that the crop had not been inadvertently contaminated. The same is true of non-GMO certification. No analysis of purity is required.
  • Organically grown, non-GMOcrops that are used as ingredients for supplements can still be contaminated if the air, soil or water is contaminated from any nearby pollution source. For example, ground water pollution is the major source of the heavy metal contamination often seen in rice-derived ingredients.
  • Organically grown, non-GMO crops can even become contaminated by PAHs if they are grown next to a busy highway.
  • Even if the ingredients are pure to begin with, PAH contamination can be introduced during processing.

What does all of this mean to us? It means that it is absolutely imperative that we do our due diligence and only choose supplement manufacturers whose quality control standards far exceed what is required of the industry. Our health just may depend on it.

 

The Bottom Line

 

  • A recent study has reported that 72% of herbal and botanical supplements, fish and edible oil food supplements, and supplements derived from bees sold in the EU were contaminated with high levels of cancer causing polycyclic aromatic hydrocarbons (PAHs).
  • The levels of PAHs in many of these products far exceeded standards recently enacted by the EU. If those supplements were taken as recommended, the daily intake of PAHs by people consuming them would also far exceed the safe limits of exposure to these toxic chemicals set in place by the International Agency for Research on Cancer.
  • While all of this sounds bad enough, the news is even worse for most of us living in the US.
  • PAHs are just the tip of the iceberg. Many supplements are also contaminated with PCBs and heavy metals.
  • The US regulates PAHs in our water supply, but does not currently regulate PAHs in our supplements. That means that manufacturers that make products primarily for consumption in the US have no incentive to test their products for PAH contamination. Most of them have no idea whether their products are safe or not.
  • There is no guarantee that even products labeled Certified Organic and Non-GMO are free of PAH contamination.
  • What does all of this mean to us? It means that it is absolutely imperative that we do our due diligence and only choose supplements manufacturers whose quality control standards far exceed what is required of the industry. Our health just may depend on it.  Remember, PAHs are not the only potential problem.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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A Low Carb Diet and Weight Loss

Posted January 15, 2019 by Dr. Steve Chaney

Do Low-Carb Diets Help Maintain Weight Loss?

Author: Dr. Stephen Chaney

 

low carb dietTraditional diets have been based on counting calories, but are all calories equal? Low-carb enthusiasts have long claimed that diets high in sugar and refined carbs cause obesity. Their hypothesis is based on the fact that high blood sugar levels cause a spike in insulin levels, and insulin promotes fat storage.

The problem is that there has been scant evidence to support that hypothesis. In fact, a recent meta-analysis of 32 published clinical studies (KD Hall and J Guo, Gastroenterology, 152: 1718-1727, 2017 ) concluded that low-fat diets resulted in a higher metabolic rate and greater fat loss than isocaloric low-carbohydrate diets.

However, low-carb enthusiasts persisted. They argued that the studies included in the meta-analysis were too short to adequately measure the metabolic effects of a low-carb diet. Recently, a study has been published in the British Medical Journal (CB Ebbeling et al, BMJ 2018, 363:k4583 ) that appears to vindicate their position.

Are low carb diets best for long term weight loss?

Low-carb enthusiasts claim the study conclusively shows that low-carb diets are best for losing weight and for keeping it off once you have lost it. They are saying that it is time to shift away from counting calories and from promoting low-fat diets and focus on low-carb diets instead if we wish to solve the obesity epidemic. In this article I will focus on three issues:

  • How good was the study?
  • What were its limitations?
  • Are the claims justified?

 

How Was The Study Designed?

low carb diet studyThe investigators started with 234 overweight adults (30% male, 78% white, average age 40, BMI 32) recruited from the campus of Framingham State University in Massachusetts. All participants were put on a diet that restricted calories to 60% of estimated needs for 10 weeks. The diet consisted of 45% of calories from carbohydrate, 30% from fat, and 25% from protein. [So much for the claim that the study showed low-carb diets were more effective for weight loss. The diet used for the weight loss portion of the diet was not low-carb.]

During the initial phase of the study 161 of the participants achieved 10% weight loss. These participants were randomly divided into 3 groups for the weight maintenance phase of the study.

  • The diet composition of the high-carb group was 60% carbohydrate, 20% fat, and 20% protein.
  • The diet composition of the moderate-carb group was 40% carbohydrate, 40% fat, and 20% protein.
  • The diet composition of the low-carb group was 20% carbohydrate, 60% fat, and 20% protein.

Other important characteristics of the study were:

  • The weight maintenance portion of the study lasted 5 months – much longer than any previous study.
  • All meals were designed by dietitians and prepared by a commercial food service. The meals were either served in a cafeteria or packaged to be taken home by the participants.
  • The caloric content of the meals was individually adjusted on a weekly basis so that weight was kept within a ± 4-pound range during the 5-month maintenance phase.
  • Sugar, saturated fat, and sodium were limited and kept relatively constant among the 3 diets.

120 participants made it through the 5-month maintenance phase.

 

Do Low-Carb Diets Help Maintain Weight Loss?

low carb diet maintain weight lossThe results were striking:

  • The low-carb group burned an additional 278 calories/day compared to the high-carb group and 131 calories/day more than the moderate-carbohydrate group.
  • These differences were even higher for those individuals with higher insulin secretion at the beginning of the maintenance phase of the study.
  • These differences lead the authors to hypothesize that low-carb diets might be more effective for weight maintenance than other diets.

 

What Are The Pros And Cons Of This Study?

low carb diet pros and consThis was a very well-done study. In fact, it is the most ambitious and well-controlled study of its kind. However, like any other clinical study, it has its limitations. It also needs to be repeated.

The pros of the study are obvious. It was a long study and the dietary intake of the participants was tightly controlled.

As for cons, here are the three limitations of the study listed by the authors:

#1: Potential Measurement Error: This section of the paper was a highly technical consideration of the method used to measure energy expenditure. Suffice it to say that the method they used to measure calories burned per day may overestimate calories burned in the low-carb group. That, of course, would invalidate the major findings of the study. It is unlikely, but it is why the study needs to be repeated using a different measure of energy expenditure.

#2: Compliance: Although the participants were provided with all their meals, there was no way of being sure they ate them. There was also no way of knowing whether they may have eaten other foods in addition to the food they were provided. Again, this is unlikely, but cannot be eliminated from consideration.

#3: Generalizability: This is simply an acknowledgement that the greatest strength of this study is also its greatest weakness. The authors acknowledged that their study was conducted in such a tightly controlled manner it is difficult to translate their findings to the real world. For example:

  • Sugar and saturated fat were restricted and were at very similar levels in all 3 diets. In the real world, people consuming a high-carb diet are likely to consume more sugar than people in the other diet groups. Similarly, people consuming the low-carb diet are likely to consume more saturated fat than people in the other diet groups.
  • Weight was kept constant in the weight maintenance phase by constantly adjusting caloric intake. Unfortunately, this seldom happens in the real world. Most people gain weight once they go off their diet – and this is just as true with low-carb diets as with other diets.
  • The participants had access to dietitian-designed prepared meals 3 times a day for 5 months. This almost never happens in the real world. The authors said “…these results [their data] must be reconciled with the long-term weight loss trials relying on nutrition education and behavioral counseling that find only a small advantage for low carbohydrate compared with low fat diets according to several recent meta-analyses.” [I would add that in the real world, people do not even have access to nutritional education and behavioral modification.]

 

low carb diet and youWhat Does This Study Mean For You?

  • This study shows that under very tightly controlled conditions (dietitian-prepared meals, sugar and saturated fat limited to healthy levels, calories continually adjusted so that weight remains constant) a low-carb diet burns more calories per day than a moderate-carb or high-carb diet. These findings show that it is theoretically possible to increase your metabolic weight and successfully maintain a healthy weight on a low-carb diet. These are the headlines you probably saw. However, a careful reading of the study provides a much more nuanced viewpoint. For example, the fact that the study conditions were so tightly controlled makes it difficult to translate these findings to the real world.
  • In fact, the authors of the study acknowledged that multiple clinical studies show this almost never happens in the real world. These studies show that most people regain the weight they have lost on low-carb diets. More importantly, the rate of weight regain is virtually identical on low-carb and low-fat diets. Consequently, the authors of the current study concluded “…translation [of their results to the real world] requires exploration in future mechanistic oriented research.” Simply put, the authors are saying that more research is needed to provide a mechanistic explanation for this discrepancy before one can make recommendations that are relevant to weight loss and weight maintenance in the real world.
  • The authors also discussed the results of their study in light of a recent, well-designed 12-month study (CD Gardener et al, JAMA, 319: 667-669, 2018 ) that showed no difference in weight change between a healthy low-fat versus a healthy low-carbohydrate diet. That study also reported that the results were unaffected by insulin secretion at baseline. The authors of the current study noted that “…[in the previous study] participants were instructed to minimize or eliminate refined grains and added sugars and maximize intake of vegetables. Probably for this reason, the reported glycemic load [effect of the diet on blood sugar levels] of the low-fat diet was very low…and similar to [the low-carb diet].” In short, the authors of the current study were acknowledging that diets which focus on healthy, plant-based carbohydrates and eliminate sugar, refined grains, and processed foods may be as effective as low-carb diets for helping maintain a healthy weight.
  • This would also be consistent with previous studies showing that primarily plant-based, low-carb diets are more effective at maintaining a healthy weight and better health outcomes long-term than the typical American version of the low-fat diet, which is high in sugar and refined grains. In contrast, meat-based, low-carb diets are no more effective than the American version of the low-fat diet at preventing weight gain and poor health outcomes. I have covered these studies in detail in my book “Slaying The Food Myths.”

Consequently, the lead author of the most recent study has said: “The findings [of this study] do not impugn whole fruits, beans and other unprocessed carbohydrates. Rather, the study suggests that reducing foods with added sugar, flour, and other refined carbohydrates could help people maintain weight loss….” This is something we all can agree on, but strangely this is not reflected in the headlines you may have seen in the media.

The Bottom Line

 

  • A recent study compared the calories burned per day on a low-carb, moderate-carb, and high-carb diet. The study concluded that the low-carb diet burned significantly more calories per day than the other two diets and might be suitable for long-term weight control. If confirmed by subsequent studies, this would be the first real evidence that low-carb diets are superior for maintaining a healthy weight.
  • However, the study has some major limitations. For example, it used a methodology that may overestimate the benefits of a low-carb diet, and it was performed under tightly controlled conditions that can never be duplicated in the real world. As acknowledged by the authors, this study is also contradicted by multiple previous studies. Further studies will be required to confirm the results of this study and show how it can be applied in the real world.
  • In addition, the kind of carbohydrate in the diet is every bit as important as the amount of carbohydrate. The authors acknowledge that the differences seen in their study apply mainly to carbohydrates from sugar, refined grains, and processed foods. They advocate diets with low glycemic load (small effects on blood sugar and insulin levels) and acknowledge this can also be achieved by incorporating low-glycemic load, plant-based carbohydrates into your diet. This is something we all can agree on, but strangely this is not reflected in the headlines you may have seen in the media.
  • Finally, clinical studies report averages, but none of us are average. When you examine the data from the current study, it is evident that some participants burned more calories per hour on the high-carb diet than other participants did on the low carb diet. That reinforces the observation that some people lose weight more effectively on low-carb diets while others lose weight more effectively on low-fat diets. If you are someone who does better on a low-carb diet, the best available evidence suggests you will have better long-term health outcomes on a primarily plant-based, low-carb diet such as the low-carb version of the Mediterranean diet.

For more details read the article above.

 

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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