Chunky Whole-Grain Chocolate Chip Cookies
And, what you need to know about heavy metals in dark chocolate
Hello friends! It’s Valentine’s day, what I like to think of as a chocolate-centric holiday. I’m making a batch of the Chunky Whole-Grain Chocolate Chip Cookies from the book and sharing the recipe with you here. Do you celebrate Valentine’s Day? If so, do you prefer to go out to dinner or stay home and cook? I’d love to hear what’s on your menu.
Today also marks the deadline Consumer Reports gave to four major chocolate companies to clean up their products. You may have read about how 23 of 28 popular brands of dark chocolate bars tested had concerning levels of heavy metals.
Dark chocolate lovers, I am here to help! I’ve scoured the literature to come up with a list of chocolate brands with minimal heavy metal exposure and maximum brain health benefits. First, let’s take a look at why dark chocolate is a brain-healthy food.
Dark chocolate provides flavanols, fiber, and magnesium for your brain
Dark chocolate (more than 70% cacao) provides a key dietary ingredient known to be important for preventing Alzheimer’s: flavanol. A member of the flavonoid family of plant nutrients, flavanols are potent anti-inflammatory substances that can improve blood vessel function and block oxidative stress. (Read more about the science supporting flavonoids for brain health in this newsletter.)
A good rule of thumb: the higher the cacao content of a chocolate, the more flavanols it provides. Darker chocolate also gives you a good dose of magnesium and selenium, not to mention 3 grams of fiber in each ounce.
The brain health benefit from dark chocolate probably comes from its ability to lower blood pressure. A healthy blood pressure at mid-life is a known factor in reducing Alzheimer’s disease decades later. Some studies also suggest a link between chocolate intake and improved cognitive function. Researchers are still figuring out if the flavanols in dark chocolate directly (or indirectly through the gut microbiome) help people perform better on cognitive tests. So far, results are promising.
While dark chocolate can be part of a brain-healthy dietary pattern, its benefits should be weighed against any possible exposure to heavy metals. Recent reports alert us that many brands of dark chocolate harbor unsafe levels of two heavy metals that are harmful to the brain—cadmium and lead. Should you be concerned? It depends on a few things I’ll go into here.
Why is there lead and cadmium in my dark chocolate?
Cadmium (Cd) is a heavy metal that comes from soil. It gets absorbed through the cacao plant’s root system and becomes strewn throughout the plant. Cadmium content varies depending on the age of the cacao tree (younger ones tend to carry less) and where the cacao is grown—some regions of the world have more cadmium-contaminated soil than others.
When it comes to the lead (Pb) in your chocolate, it’s a little more complicated. Lead contamination happens at the farm—it flakes off lead paint and gets aerosolized from burning diesel gas, plastic, and garbage. The tiny lead particles cling to dust that settles on the sticky surface of cacao beans as they are harvested and left to dry in the sun. This diagram shows how farm practices are at the root of both lead and cadmium contamination of cacao.
The truth is these heavy metals don’t just contaminate cacao beans, but other foods, too, such as spinach, carrots, and sweet potatoes. (You may recall headlines last year reporting that most baby foods were contaminated with heavy metals.) Consuming too many of these metals, over time, can lead to brain health hazards. Lead, especially, is most dangerous for those with rapidly-growing brains—babies and young children—which could lead to developmental problems. The Food and Drug Administration sets levels for safe consumption (below or equal to 0.5 µg/day for lead or below 4.1 µg/day of cadmium) based on the most vulnerable members of the population—small children. In other words, these levels are conservatively low.
Here’s what you need to know about buying chocolate
Heavy metal contamination of dark chocolate is nothing new; it has been on the radar of several consumer advocacy groups for years. The most recent analysis in 2022 by Consumer Reports and As You Sow looked at hundreds of chocolate bar brands. The result: most harbor levels of lead and cadmium over the limit of what’s safe for pregnant women and children. As You Sow has filed dozens of lawsuits against some of the worst offenders (Trader Joe’s, Godiva, Hershey’s Chocolove, Theo) for failing to warn buyers their chocolate contains lead, cadmium, or both.
How much does a non-pregnant adult need to worry about getting sick from eating dark chocolate? This depends on how much and what types of chocolate you eat.
Pregnant women and children should be most careful about limiting any exposure to these metals through dark chocolate. For older brains, however, it’s not clear that this minimal exposure could lead to health problems. That’s because a mature adult brain is not nearly as sensitive to the dangers of lead and cadmium. Still, it makes sense to limit exposure, if possible. Lead, especially, can contribute to high blood pressure, kidney disease, and nervous system problems.
Chocolate with a higher percentage of cacao probably has more heavy metals. A noticeable trend: as the cacao content goes up, so does the chocolate’s heavy metal content. This makes sense since darker chocolates are made with more cacao.
Don’t lean on dark chocolate as your primary source of flavanols. You can get flavanols from other foods, too, such as pears, extra-virgin olive oil, citrus fruits, soybeans, cruciferous vegetables, leafy greens, and green tea.
Daily dark chocolate lover? Take note. According to the consumer research firm Mintel, 15% of us are daily consumers of dark chocolate. If you tend to eat more than 1 ounce of dark chocolate per day, your chocolate habit could push that limit beyond what is safe. Choose brands with lower heavy metal scores, chocolates with lower cacao percentages, and get some of your chocolate intake through tested cacao powder (Hershey’s natural unsweetened cocoa powder has scored very low in heavy metals).
If you enjoy dark chocolate every once in a while, you probably don’t need to worry about getting too much of these metals. Your cadmium and lead exposure will be below the threshold of what is considered harmful. If you keep your daily dark chocolate dose to around 1 ounce, it’s unlikely you need to be concerned about health problems from lead or cadmium.
Organic or not? Buying organic chocolate, Consumer Reports found, doesn’t translate to having lower heavy metals.
The list of best and worst chocolates for heavy metals
Based on testing by Consumer Reports and As You Sow, not all dark chocolates were found to have lead and cadmium. These brands top the brain-healthy list, both high in cacao yet low in heavy metals:
Mast Organic Dark Chocolate 80% Cacao
Valrhona Abinao Dark Chocolate, 85% Cacao
Taza Chocolate Organic Deliciously Dark Chocolate 70% Cacao
Ghirardelli Intense Dark Chocolate 86% Cacao
Ghirardelli Intense Dark Chocolate Twilight Delight 72% Cacao
Guittard Nocturne Organic Bittersweet Chocolate Baking Wafers 74 Cacao
Guittard Unsweetened Chocolate Gourmet Baking Bars
These brands tested highest in lead and cadmium:
Hershey's Special Dark Mildly Sweet Chocolate
Chocolove Extreme Dark Chocolate 88% Cocoa
Hu Organic Simple Dark Chocolate 70% Cacao
Trader Joe's Dark Chocolate 72% Cacao.
While Consumer Reports tested 28 chocolate bars, As You Sow has a more extensive list of 469 chocolate products, of which 285 scored above safe levels for cadmium and lead. (Find the full list here.) They tested cocoa powders, too. It’s a relief to know the common pantry staple Hersheys Cocoa 100% Cacao Natural Unsweetened tested minimal for heavy metals.
In addition, I did some digging to see if Crio Bru, my favorite drinkable chocolate, had been tested for heavy metals. To my delight, the company promptly sent me proof of its lead and cadmium testing results—all were minimally detected. Try Crio Bru for yourself with this Starter Kit.
Does this mean giving up your favorite chocolate if it’s on the “bad” part of the list?
Not necessarily. Just cut back on consumption to limit exposure to these heavy metals. If you are a daily chocolate consumer, stick to brands at the top of the list. Valrhona is one of my top picks for high-quality chocolate, and now it’s comforting to know it’s also low in heavy metals.
Also, following a mostly plant based brain-healthy dietary pattern will help balance any minimal exposures you may get from chocolate. That’s because a diet rich in other minerals, such as iron and calcium, are your body’s natural defense against heavy metal absorption. Some studies show that heavy metals like cadmium can be sweat out of the body during sauna use.
My quest for the ultimate healthier chocolate chip cookie
I must have made dozens of batches of these cookies when I was testing for the book. I didn’t want to skimp on decadence—that just-right combination of chewy and crispy that makes a chocolate chip cookie great. But I also wanted the cookies to maintain the brain health principles of being rich in fiber, healthy fats, and flavonoids, 3 of the 4F’s we talked about a few posts back.
Whole wheat, buckwheat, and oat bran give the cookies a range of nuanced nutty flavors, while providing a good dose of fiber. The combination of extra-virgin olive oil and tahini, a sesame seed paste, provides a brain-friendly swap for butter that adds a nice savory contrast for a not-too-sweet cookie. Almond butter, my friend Katie Morford discovered, can be swapped in for the tahini with excellent results. She also used almond flour instead of buckwheat. Thanks Katie!
I hope you love these cookies as much as I do. And please let me know if you come up with any other ingredient swaps.
RECIPE: Chunky Whole-Grain Chocolate Chip Cookies
Makes 16 cookies
¾ packed cup (180 g) light brown sugar
¾ cup (180 ml) tahini, well stirred and at room temperature
½ cup (120 ml) extra-virgin olive oil
1 teaspoon pure vanilla extract
1 spooned-and-leveled cup (140 g) whole-wheat flour
½ cup (70 g) buckwheat flour
¼ cup (40 g) oat bran cereal or ¼ cup (25 g) rolled oats
3 tablespoons cacao powder
1 teaspoon baking powder
1 teaspoon kosher salt
2 eggs
6 ounces (170 g) bittersweet chocolate (60% to 80% cacao), chopped into ½-inch (1.25 cm) chunks (or 1 cup dark chocolate chips)
Flaky salt (optional)
Set oven racks in the upper- and lower-third positions and preheat the oven to 350°F (180°C). Line two rimmed 18-by-13-inch (46 by 33 cm) baking sheets with parchment paper or silicone mats.
Whisk together the sugar, tahini, oil, and vanilla in a large bowl. Let sit for 10 minutes.
Meanwhile, whisk together the whole-wheat flour, buckwheat flour, oat cereal, cacao powder, baking powder, and kosher salt in another large bowl.
Beat the eggs one at a time into the sugar-tahini mixture, scraping down the sides of the bowl between additions, until smooth and well incorporated. Add the flour mixture to the bowl and stir until you have a thick dough with no streaks of flour remaining. Set aside 2 tablespoons of the larger pieces of chocolate to top the cookies. Add the rest of the chocolate, including any shards on the cutting board, to the cookie dough and mix until evenly combined.
Using a tablespoon measure, scoop out scant 3 tablespoons (55 g) for each cookie and roll into a 1½-inch (3.8 cm) ball, then press down to form a 2-inch-wide (5 cm) puck. Place on the prepared baking sheets leaving 3 inches (7.5 cm) between cookies, or eight to a sheet. Press a few pieces of the reserved chocolate into the tops of each cookie and sprinkle with a pinch of flaky salt (if using).
Bake for 8 to 10 minutes, or until set on the edges and still soft in the center. Let sit a few minutes then transfer to a rack to cool.
These cookies are best eaten the same day as or the day after baking. Cookie dough freezes well in an airtight container for up to 3 months. Or freeze the baked cookies, tightly wrapped, for up to 3 months.
Tips: The size here is strategic: rolling the dough into a 1½-inch (3.8 cm) ball and flattening it into a 2-inch (5 cm) puck creates a cookie that’s soft and chewy, with a slightly craggy texture. Keep a close eye on them toward the end of baking and pull from the oven when the centers are still soft.
Excerpted from The Brain Health Kitchen by Annie Fenn (Artisan Books). Copyright © 2023.
Last minute Valentine’s Day Gift?
May I suggest a gift subscription to the Brain Health Kitchen newsletter? Nothing says you care more than empowering loved ones with the information they need to take care of their brains.
Finally, I’ll leave you with this little gem of a video of my friends Nikki Deloach (the beloved actress) and Liz Humphreys (founder of the Alzheimer’s non-profit Mind What Matters) cooking the Spinach and Artichoke Dip from the book. Girlfriends are the best!
I’ll be back on Friday with upcoming dates and details of the BHK book tour in March and April: Dallas, Cincinnati, Nashville, New York City, and Boston.
Love,
Annie
Thank you for this cogent explanation of the dark chocolate debate. I knew I could count on you to clarify the issues and provide the information we all need. All that AND a great recipe perfect for Valentine's Day.
I made the cookies yesterday - fabulous! Just ate another one with my morning coffee. This could be a problem ;-) I better get the rest of the batch into the freezer ASAP.