Are Toxic Chemicals Lowering Our IQ?

Written by Dr. Steve Chaney on . Posted in Environment and Health, Issues

Is Chemical Brain Drain A Pandemic?

 Author: Dr. Stephen Chaney

In a past issue of “Health Tips From the Professor” I examined the evidence suggesting that toxic chemicals in the home could cause childhood asthma. That is alarming because asthma can predispose individuals to other diseases and affects quality of life.

Confused ChildBut, what if that were only the tip of the iceberg? For example, a recent headline stated: “More Toxic Chemicals [In Our Environment] Are Damaging Children’s Brains”. If that headline is true, it’s downright scary.

The authors of this study suggested that toxic chemicals which are abundant in our environment can cause decreases in IQ and aggressive or hyperactive behavior in children – and that those changes may be permanent.

The Study Behind The Headlines

The paper that generated the headlines (Grandjean & Landrigan, The Lancet Neurology, 13: 330-338, 2014) was a review of the literature, not an actual clinical study.

Based on published clinical studies, the authors identified 12 chemicals commonly found in the environment as developmental neurotoxins (toxins that interfere with normal brain development) based. [If you would like to find out what those “Dirty Dozen” chemicals are and where they are found, click here.]

This finding compares with 6 developmental neurotoxins that they were able to identify in a similar study in 2006.

The authors were not claiming that the number or amount of toxic chemicals changed between 2006 and 2014. They were saying that science has advanced to the point where we can classify six more chemicals that have been in our environment for years as developmental neurotoxins.

Even more worrisome, the authors postulate that many more environmental neurotoxins remain undiscovered.

Are Toxic Chemicals Lowering Our IQ?

To answer that question, you need to look at some of the studies they cited in their review. For example:

  • Elevated blood lead levels in children are associated with as much as a 7 point decrease in IQ (Lamphear et al, Environmental Health Perspectives, 113: 894-899, 2005).
  • Elevated fluoride levels in drinking water are also associated with as much as a 7 point decrease in IQ (Choi et al, Environmental Health Perspectives, 120: 1362-1368, 2012).

The effects of many of the toxic chemicals on IQ were difficult to quantify, but the authors estimated that exposure of US children to just 3 of the chemicals (lead, methymercury and organophosphate pesticides) was sufficient to lower their average IQ by 1.6 points.

What Are The Potential Consequences?

The authors spoke of the environmental neurotoxins they identified as representing a “silent pandemic of a chemical brain drain” that could cost the US economy billions of dollars.

One of the blog posts I read on this topic summarized the consequences in a very graphic manner. It said:

If one child’s IQ is reduced by 5 points, it doesn’t appear to make a big difference.  For example, that child might be:

  • A little slower to learn
  • A little shorter of attention
  • A little less successful at tests and at work

That might result in $90,000 in lost lifetime earnings

However, if the average IQ of every child in the US were decreased by 5 points, the effect becomes significant:

  • Only half as many members of the next generation would be “intellectually gifted”.
  • Twice as many of the next generation would be “intellectually impaired”
  • Lost productivity could be in the billions

Of course, statements like that are a bit over the top. Drs. Grandjean and Landrigan did not claim that the net effect of the chemicals they identified was a 5 point drop in IQ. Nor did they claim that all US children were affected equally.

Still, it’s enough to make you think.

Are Toxic Chemicals Causing Behavior Problems?

Angry boy portraitThe authors cited numerous studies linking the chemical neurotoxins they identified to aggression and hyperactivity. But perhaps the most compelling reason to suspect that environmental chemicals may be affecting brain development is the spiraling incidence of developmental disorders such as autism and ADHD. For example:

  • Autism has increased by 78% since 2007 and now affects 1 of 88 eight year old children.
  • ADHD has increased by 43% since 2003 and now affects 11% of children age 4-17.

Some of this increase could be due to better diagnosis of these conditions, but nobody believes that all of it is due to improved diagnosis. The authors claim that much of this increase is likely due to environmental exposure to the kinds of developmental neurotoxins they identified.

Is The Science Solid?

This is a difficult area of research. You can’t do the gold standard double-blind, placebo-controlled clinical trial. Nobody in their right mind would give one group of children toxic chemicals and the other group a placebo.

The studies cited in this paper were mostly population studies. Basically this means that they compared children with exposure to certain toxic chemicals to a control group that was as similar as possible to the first group except that their exposure to the toxic chemicals was less.

The limitation of this kind of study is obvious. We are usually comparing children from different locations or of different backgrounds. We almost never know if we have controlled for all possible variables so that the groups are truly identical.

As a consequence it becomes important to ask how many studies come to the same conclusion. For some of the toxic chemicals, such as lead, methymercury and organophosphate pesticides, the weight of evidence is very strong. For some of the newer additions to their list of developmental neurotoxins, it is pretty clear that the chemicals have neurotoxic properties, but the significance of those effects on the developing human brain are hard to quantify at this point.

The Bottom Line:

1)     A recent review claims that there is a good scientific basis for classifying at least 12 environmental chemicals as developmental neurotoxins that are likely to reduce IQ and contribute to behavioral problems in US children. [If you would like to find out what those “Dirty Dozen” chemicals are and where they are found, click here.]

2)     The science behind the claims in this review is solid, but not iron-clad.

3)     However, there are times when we need to simply ask ourselves: “What if it were true?” The consequences of lowered IQ and developmental behavioral problems are so significant that it may not make sense to wait until we have unassailable scientific evidence before we act.

4)     We all need to be guardians of our personal environment. But, it is not easy. The “Dirty Dozen” chemicals identified in this study come from many sources:

  • Some are industrial pollutants. For those, we need lobby for better environmental regulation.
  • Some are persistent groundwater contaminants. For those we need to drink purified water whenever possible.
  • Some are insecticides and herbicides used in agriculture. For those we need to buy organic, locally grown produce when feasible.
  • Some are found in common household products and furnishings. For those we need to become educated label readers and use non-toxic products in our home whenever possible.

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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What Is The Planetary Diet?

Posted May 21, 2019 by Dr. Steve Chaney

Is Your Diet Destroying The Planet?

Author: Dr. Stephen Chaney

 

Earth Day has come and gone, but you are still committed to saving the planet. You save energy. You recycle. You drive an electric car. But is your diet destroying the planet?

This is not a new question, but a recent commission of international scientists has conducted a comprehensive study into our diet and its effect on our health and our environment. Their report (W. Willet et al, The Lancet, 393, issue 10170, 447-492, 2019 ) serves as a dire warning of what will happen if we don’t change our ways. I touched on this report briefly in a previous issue of “Health Tips From The Professor,” What Is The Flexitarian Diet , but this topic is important enough that it deserves an issue all its own.

The commission carefully evaluated diet and food production methods and asked three questions:

  • Are they good for us?
  • Are they good for the planet?
  • Are they sustainable? Will they be able to meet the needs of the projected population of 10 billion people in 2050 without degrading our environment.

The commission described the typical American diet as a “lose-lose diet.” It is bad for our health. It is bad for the planet. And it is not sustainable.

In its place they carefully designed their version of a primarily plant-based diet they called a “win-win diet.”  It is good for our health. It is good for the planet. And, it is sustainable.

In their publication they refer to their diet as the “universal healthy reference diet” (What else would you expect from a committee?). However, it has become popularly known as the “Planetary Diet.”

I have spoken before about the importance of a primarily plant-based diet for our health. In that context it is a personal choice. It is optional.

However, this report is a wake-up call. It puts a primarily plant-based diet in an entirely different context. It is essential for the survival of our planet. It is no longer optional.

If you care about global warming…If you care about saving our planet, there is no other choice.

How Was The Study Done?

The study (W. Willet et al, The Lancet, 393, issue 10170, 447-492, 2019 ) was the report of the EAT-Lancet Commission on Healthy Diets from Sustainable Food Systems. This Commission convened 30 of the top experts from across the globe to prepare a science-based evaluation of the effect of diet on both health and sustainable food production through the year 2050. The Commission included world class experts on healthy diets, agricultural methods, climate change, and earth sciences. The Commission reviewed 356 published studies in preparing their report.

 

Is Your Diet Destroying The Planet?

When they looked at the effect of food production on the environment, the Commission concluded:

  • “Strong evidence indicates that food production is among the largest drivers of global environmental change.” Specifically, the commission reported:
  • Agriculture occupies 40% of global land (58% of that is for pasture use).
  • Food production is responsible for 30% of global greenhouse gas emissions and 70% of freshwater use.
  • Conversion of natural ecosystems to croplands and pastures is the largest factor causing species to be threatened with extinction. Specifically, 80% of extinction threats to mammals and bird species are due to agricultural practices.
  • Overuse and misuse of nitrogen and phosphorous in fertilizers causes eutrophication. In case you are wondering, eutrophication is defined as the process by which a body of water becomes enriched in dissolved nutrients (such as phosphates from commercial fertilizer) that stimulate the growth of algae and other aquatic plant life, usually resulting in the depletion of dissolved oxygen. This creates dead zones in lakes and coastal regions where fish and other marine organisms cannot survive.
  • About 60% of world fish stocks are fully fished and more than 30% are overfished. Because of this, catch by global marine fisheries has been declining since 1996.
  • “Reaching the Paris Agreement of limiting global warming…is not possible by only decarbonizing the global energy systems. Transformation to healthy diets from sustainable food systems is essential to achieving the Paris Agreement.”
  • The world’s population is expected to increase to 10 billion by 2050. The current system of food production is unsustainable.

When they looked at the effect of the foods we eat on the environment, the Commission concluded:

  • Beef and lamb are the biggest contributors to greenhouse gas emissions and land use.
  • The concern about land use is obvious because of the large amount of pasture land required to raise cattle and sheep.
  • The concern about greenhouse gas emissions is because cattle and sheep are ruminants. They not only breathe out CO2, but they also release methane into the atmosphere from fermentation in their rumens of the food they eat. Methane is a potent greenhouse gas, and it persists in the atmosphere 25 times longer than CO2. The single most important thing we can do as individuals to reduce greenhouse gas emissions is to eat less beef and lamb. [Note: grass fed cattle produce more greenhouse gas emissions than cattle raised on corn because they require 3 years to bring to market rather than 2 years.]
  • In terms of energy use beef, lamb, pork, chicken, dairy and eggs all require much more energy to produce than any of the plant foods.
  • In terms of eutrophication, beef, lamb, and pork, all cause much more eutrophication than any plant food. Dairy and eggs cause more eutrophication than any plant food except fruits.
  • In contrast, plant crops reduce greenhouse gas emissions by removing CO2 from the atmosphere.

 

What Is The Planetary Diet?

In the words of the Commission: “[The Planetary Diet] largely consists of vegetables, fruits, whole grains, legumes, nuts, and unsaturated oils. It includes a low to moderate amount of seafood, poultry, and eggs. It includes no or a very low amount of red meat, processed meat, sugar, refined grains, and starchy vegetables.”

When described in that fashion it sounds very much like other healthy diets such as semi-vegetarian, Mediterranean, DASH, and Flexitarian. However, what truly distinguishes it from the other diets is the restrictions placed on the non-plant portion of the diet to make it both environmentally friendly and sustainable. Here is a more detailed description of the diet:

  • It starts with a vegetarian diet. Vegetables, fruits, beans, nuts, soy foods, and whole grains are the foundation of the diet.
  • It allows the option of adding one serving of dairy a day (It turns out that cows produce much less greenhouse emissions per serving of dairy than per serving of beef. That’s because cows take several years to mature before they can be converted to meat, and they are emitting greenhouse gases the entire time).
  • It allows the option of adding one 3 oz serving of fish or poultry or one egg per day.
  • It allows the option of swapping seafood, poultry, or egg for a 3 oz serving of red meat no more than once a week. If you want a 12 oz steak, that would be no more than once a month.

This is obviously very different from the way most Americans currently eat. According to the Commission:

  • “This would require greater than 50% reduction in consumption of unhealthy foods, such as red meat and sugar, and greater than 100% increase in the consumption of healthy foods, such as nuts, fruits, vegetables, and legumes.”
  • “In addition to the benefits for the environment, “dietary changes from current diets to healthy diets are likely to substantially benefit human health, averting about 10.8-11.6 million deaths per year globally.”

What Else Did The Commission Recommend?

In addition to changes in our diets, the Commission also recommended several changes in the way food is produced. Here are a few of them.

  • Reduce greenhouse gas emissions from the fuel used to transport food to market.
  • Reduce food losses and waste by at least 50%.
  • Make radical improvements in the efficiency of fertilizer and water use. In terms of fertilizer, the change would be two-fold:
    • In developed countries, reduce fertilizer use and put in place systems to capture runoff and recycle the phosphorous.
    • In third world countries, make fertilizer more available so that crop yields can be increased, something the Commission refer to as eliminating the “yield gap” between third world and developed countries.
  • Stop the expansion of new agricultural land use into natural ecosystems and put in place policies aimed at restoring and re-foresting degraded land.
  • Manage the world’s oceans effectively to ensure that fish stocks are used responsibly and global aquaculture (fish farm) production is expanded sustainability.

What we can do: While most of these are government level policies, we can contribute to the first three by reducing personal food waste and purchasing organic produce locally whenever possible.

What Does This Mean For You?

If you are a vegan, you are probably asking why the Commission did not recommend a completely plant-based diet. The answer is that a vegan diet is perfect for the health of our planet. However, the Commission wanted to make a diet that was as consumer-friendly as possible and still meet their goals of a healthy, environmentally friendly, and sustainable diet.

If you are eating a typical American diet or one of the fad diets that encourage meat consumption, you are probably wondering how you can ever make such drastic changes to your diet. The answer is “one step at a time.”  If you have read my books “Slaying The Food Myths” or “Slaying the Supplement Myths,”  you know that my wife and I did not change our diet overnight. Our diet evolved to something very close to the Planetary Diet over a period of years.

The Commission also purposely designed the Planetary Diet so that you “never have to say never” to your favorite foods. Three ounces of red meat a week does not sound like much, but it allows you a juicy steak once a month.

Sometimes you just need to develop a new mindset. As I shared in my books, my father prided himself on grilling the perfect steak. I love steaks, but I decided to set a few parameters. I don’t waste my red meat calories on anything besides filet mignon at a fine restaurant. It must be a special occasion, and someone else must be buying. That limits it to 2-3 times a year. I still get to enjoy good steak, and I stay well within the parameters of the Planetary diet.

Develop your strategy for enjoying some of your favorite foods within the parameters of the Planetary Diet and have fun with it.

The Bottom Line

 

Is your diet destroying the planet? This is not a new question, but a recent commission of international scientists has conducted a comprehensive study into our diet and its effect on our health and our environment. Their report serves as a dire warning of what will happen to us and our planet if we don’t change our ways.

The Commission carefully evaluated diet and food production methods and asked three questions:

  • Are they good for us?
  • Are they good for the planet?
  • Are they sustainable? Will they be able to meet the needs of the projected population of 10 billion people in 2050 without degrading our environment.

The Commission described the typical American diet as a “lose-lose diet.”  It is bad for our health. It is bad for the planet. And it is not sustainable.

In its place they carefully designed their version of a primarily plant-based diet they called a “win-win diet.”  It is good for our health. It is good for the planet. And, it is sustainable.

In their publication they refer to their diet as the “universal healthy reference diet” (What else would you expect from a committee?). However, it has become popularly known as the “Planetary Diet.”

The Planetary Diet is similar to other healthy diets such as semi-vegetarian, Mediterranean, DASH, and Flexitarian. However, what truly distinguishes it from the other diets is the restrictions placed on the non-plant portion of the diet to make it both environmentally friendly and sustainable (for details, read the article above).

I have spoken before about the importance of a primarily plant-based diet for our health. In that context it is a personal choice. It is optional.

However, this report is a wake-up call. It puts a primarily plant-based diet in an entirely different context. It is essential for the survival of our planet. It is no longer optional.

If you care about global warming…If you care about saving our planet, there is no other choice.

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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