Unsweetened cocoa powder, including Hershey’s, is one of the most nutrient-dense foods you can add to your diet, but the specific product you pick off the shelf matters more than the brand name. Hershey’s sells two main varieties: a natural cocoa powder and a Dutch-processed version marketed as “Special Dark.” That processing distinction dramatically changes the flavanol content, which is the compound behind most of cocoa’s researched health benefits. The story is more nuanced than “cocoa powder is a superfood,” and it involves some real downsides worth knowing about.
Why the Type of Processing Changes Everything
Cocoa beans are naturally acidic and bitter. To mellow the flavor and darken the color, manufacturers sometimes treat cocoa with an alkaline solution, a step called Dutch processing or alkalization. Hershey’s standard cocoa powder is natural (non-alkalized), while Hershey’s Special Dark is Dutch-processed. That distinction is not just cosmetic. A study analyzing a range of commercial cocoa powders found that natural, non-alkalized powders contained an average of about 35 mg/g of total flavanols, while lightly processed powders dropped to around 14 mg/g, medium-processed powders fell to about 8 mg/g, and heavily processed powders retained only about 4 mg/g.1PubMed. Impact of alkalization on the antioxidant and flavanol content of commercial cocoa powders That means heavy Dutch processing can strip out roughly 90% of the flavanols compared to natural cocoa.
Separate research confirmed the pattern and found that alkalization caused about a 60% loss of total flavonoid content on average. Epicatechin, the specific compound most closely linked to cocoa’s vascular benefits, took an even bigger hit, declining by about 67%. Quercetin, another beneficial compound, dropped by 86%.2Journal of Agricultural and Food Chemistry. Flavanol and Flavonol Contents of Cocoa Powder Products: Influence of the Manufacturing Process So if you are reaching for cocoa powder specifically for health reasons, the natural version is the clear winner. Hershey’s standard (non-Special Dark) cocoa is natural, which puts it in the higher-flavanol category.
Blood Pressure and Heart Health
The cardiovascular evidence for cocoa flavanols is among the strongest in the field. A Cochrane systematic review pooling 40 treatment comparisons across roughly 1,800 participants found that flavanol-rich cocoa products produced a small but statistically significant drop in blood pressure: about 1.8 mmHg for both systolic and diastolic readings over study periods averaging around nine weeks.3PubMed Central. Effect of cocoa on blood pressure That might sound modest, but at a population level, even a 2-point reduction in average blood pressure is associated with meaningful reductions in stroke and heart disease risk.
The mechanism appears to center on nitric oxide. Research in healthy men showed that ingesting flavanol-rich cocoa acutely raised circulating nitric oxide levels, improved the ability of arteries to dilate, and enhanced microcirculation. When the researchers isolated pure epicatechin and gave it to participants, it closely mimicked the vascular effects of the whole cocoa drink, which strongly suggests epicatechin is the active ingredient driving these benefits.4PubMed Central. (-)-Epicatechin mediates beneficial effects of flavanol-rich cocoa on vascular function in humans When nitric oxide synthase was chemically blocked, the benefit disappeared, confirming the pathway.
One wrinkle involves theobromine, the mild stimulant naturally present in cocoa. At natural doses found in a typical cocoa serving, theobromine did not significantly change blood pressure. But when researchers tested a theobromine-enriched cocoa, 24-hour ambulatory systolic blood pressure actually rose by about 3 mmHg compared to placebo, even though central blood pressure measured in the lab dropped.5PubMed. Effects on peripheral and central blood pressure of cocoa with natural or high-dose theobromine: a randomized, double-blind crossover trial The practical takeaway: a tablespoon or two of cocoa powder in your morning smoothie is not going to flood you with enough theobromine to worry about, but concentrated theobromine supplements are a different story.
Insulin Sensitivity, Cholesterol, and Metabolic Effects
Beyond blood pressure, cocoa flavanols appear to influence how your body handles sugar and fat. A controlled trial in people with hypertension found that dark chocolate (rich in cocoa flavanols) improved insulin resistance, lowered LDL cholesterol from roughly 3.4 to 3.0 mmol/L, and improved endothelial function, while white chocolate (which lacks flavanols) did not.6PubMed. Cocoa reduces blood pressure and insulin resistance and improves endothelium-dependent vasodilation in hypertensives The effect was attributed to the flavanol content rather than other components of the cocoa.
A broader review of research on cocoa and type 2 diabetes found that most studies pointed toward an anti-diabetic effect, with flavonoids appearing to enhance insulin secretion, improve insulin sensitivity in peripheral tissues, and reduce oxidative and inflammatory damage associated with the disease.7PubMed Central. Effects of Cocoa Antioxidants in Type 2 Diabetes Mellitus These findings are encouraging but come with a caveat: most of the metabolic studies used concentrated flavanol doses or dark chocolate, not necessarily the amount you would get from a tablespoon of cocoa powder stirred into oatmeal. The direction of the evidence is positive, but the magnitude of any benefit from typical cocoa powder servings in otherwise healthy people remains uncertain.
There is also some preliminary evidence that cocoa may influence appetite. A randomized crossover trial found that a dark-chocolate preload reduced hunger sensations after a meal, and a four-week dark-chocolate intervention increased short-chain fatty acids (acetate and propionate) associated with satiety signaling.8Journal of Functional Foods. Effects of dark-chocolate on appetite variables and glucose tolerance: A 4 week randomised crossover intervention in healthy middle aged subjects Interestingly, postprandial glucose and insulin went up rather than down in that study, which the researchers themselves flagged as requiring further investigation. The appetite effects are real but not yet well understood.
Inflammation and C-Reactive Protein
Chronic low-grade inflammation underlies many diseases, so it would be meaningful if cocoa could dial it down. The picture here is mixed. A critical review of randomized controlled trials found that in healthy people, regular cocoa consumption generally did not change most circulating inflammatory markers like IL-6, TNF-α, or CRP. However, in people with type 2 diabetes or impaired fasting glucose, several inflammatory markers did decrease.9PubMed Central. Impact of Cocoa Consumption on Inflammation Processes—A Critical Review of Randomized Controlled Trials This suggests that cocoa’s anti-inflammatory effects may be more pronounced in people who already have elevated inflammation.
A large observational study in a healthy Italian population found that regular dark chocolate consumers had lower C-reactive protein concentrations than non-consumers, with a geometric mean of 1.14 mg/L compared to 1.29 mg/L, an association that held across multiple statistical adjustments.10The Journal of Nutrition. Regular Consumption of Dark Chocolate Is Associated with Low Serum Concentrations of C-Reactive Protein in a Healthy Italian Population Observational data cannot prove cause, but it is consistent with the broader flavanol story.
Cognitive Effects
A review of research on cocoa and brain function found dose-dependent improvements in general cognition, attention, processing speed, and working memory across multiple studies. One striking finding was that cocoa flavanols appeared to protect cognitive performance specifically impaired by sleep deprivation, suggesting both a long-term neuroprotective role and a more immediate functional benefit.11PubMed Central. Enhancing Human Cognition with Cocoa Flavonoids The researchers were careful to note this field is still preliminary, but the consistency of the direction is encouraging.
It is worth separating the cognitive effects of flavanols from the effects of cocoa’s stimulants. Cocoa powder contains both theobromine and a small amount of caffeine. Research comparing the two found that caffeine increased self-reported alertness for several hours, while theobromine on its own actually decreased calmness without boosting alertness. When the two were combined, the mood effects resembled caffeine alone.12Physiology & Behavior. Differential contributions of theobromine and caffeine on mood, psychomotor performance and blood pressure A single tablespoon of cocoa powder typically contains only about 12 mg of caffeine, roughly a tenth of a cup of coffee, so the stimulant effect is mild.
Gut Health and Prebiotic Effects
Cocoa polyphenols interact with gut bacteria in a way that resembles a prebiotic. A review of the bidirectional relationship between cocoa polyphenols and the gut microbiota found that these compounds promote the growth of beneficial bacteria like Lactobacillus and Bifidobacterium while reducing pathogenic species like Clostridium perfringens.13PubMed Central. Cocoa Polyphenols and Gut Microbiota Interplay: Bioavailability, Prebiotic Effect, and Impact on Human Health This is relevant because the gut bacteria in turn break down cocoa polyphenols into smaller metabolites that the body can absorb, creating a feedback loop where each side benefits the other.
Animal research has confirmed the scale of these effects. In a pig study, cocoa powder supplementation led to a seven-fold increase in Lactobacillus species in feces and a nine-fold increase in Bifidobacterium in the proximal colon.14The Journal of Nutrition. Flavanol-Enriched Cocoa Powder Alters the Intestinal Microbiota, Tissue and Fluid Metabolite Profiles, and Intestinal Gene Expression in Pigs An in vitro model also found that cacao treatment significantly increased several beneficial bacterial genera in certain gut microbiota profiles.15PubMed Central. Modulation of Gut Microbiota by Cacao: Insights from an In Vitro Model The fiber in cocoa powder (about 2 grams per tablespoon) likely contributes to these prebiotic effects alongside the polyphenols.
Skin Protection
Some of the more surprising cocoa research involves skin health. A 12-week trial in women found that daily consumption of a high-flavanol cocoa drink reduced UV-induced redness by 15% after six weeks and 25% after twelve weeks, while a low-flavanol cocoa drink produced no change. The high-flavanol group also saw increased skin blood flow, greater skin density, better hydration, and decreased roughness and scaling.16PubMed. Long-term ingestion of high flavanol cocoa provides photoprotection against UV-induced erythema and improves skin condition in women
A longer 24-week trial in photo-aged women confirmed part of this story. The cocoa flavanol group showed a significantly increased minimal erythemal dose (the UV threshold for reddening), meaning their skin had become more resistant to sun damage compared to placebo.17The Journal of Nutrition. Cocoa Flavanol Supplementation Influences Skin Conditions of Photo-Aged Women: A 24-Week Double-Blind, Randomized, Controlled Trial This is not a replacement for sunscreen, but it suggests flavanol-rich cocoa offers some internal photoprotection over time.
Getting the Most Out of It
How you consume cocoa powder affects how much of the good stuff your body actually absorbs. Flavanol metabolites appear in the blood within about an hour to an hour and a half after consumption, with clearance extending out to around eight hours.18PubMed Central. Flavanol Bioavailability in Two Cocoa Products with Different Phenolic Content: A Comparative Study in Humans One study found that consuming cocoa alongside carbohydrate-rich foods like bread or sugar increased flavanol absorption to about 140% of baseline levels, with flavanol uptake positively correlated with the carbohydrate content of the meal. Fat- and protein-rich meals did not have the same boosting effect.19Life Sciences. Food effects on the absorption and pharmacokinetics of cocoa flavanols
A common concern is whether milk blocks cocoa’s benefits. Research directly testing this found that milk protein did not reduce the average concentration of polyphenols in the blood. It slightly shifted the timing of absorption, speeding it up early and slowing it later, but this had no physiological significance.20PubMed. The effect of milk protein on the bioavailability of cocoa polyphenols So mixing cocoa powder into milk, yogurt, or a smoothie should not undermine the flavanol benefits.
As for shelf life, you do not need to worry about flavanol degradation in a sealed container. Research found that antioxidant activity and flavanol levels in cocoa powder remain stable over typical shelf lives of a year under controlled storage, and even over two years in ambient conditions. Remarkably, 80-year-old cocoa powder and 116-year-old cocoa beans still showed very high flavanol content.21Journal of Agricultural and Food Chemistry. Stability of Cocoa Antioxidants and Flavan-3-ols over Time
Heavy Metal Contamination
Here is where the health story gets less rosy. Cocoa plants are efficient at absorbing cadmium from soil, and lead contamination can occur during drying, storage, and processing. A multi-year analysis of 72 dark chocolate and cocoa products sold in the United States found that the average lead and cadmium per listed serving exceeded California’s Proposition 65 limits. About 43% of products tested exceeded the lead threshold, and 35% exceeded the cadmium threshold. However, the median concentrations fell below those same limits, suggesting that a handful of outlier products were skewing the averages upward.22PubMed Central. A multi-year heavy metal analysis of 72 dark chocolate and cocoa products in the USA Arsenic levels were consistently well below safety limits across all products tested.
A separate analysis of cocoa powder and chocolate specifically found maximum metal concentrations of about 0.3 mg/kg for cadmium, 1.2 mg/kg for lead, and 0.09 mg/kg for arsenic in cocoa powder.23Food Chemistry. Toxic metal levels in cocoa powder and chocolate by ICP-MS method after microwave-assisted digestion To put this in practical terms: a tablespoon of cocoa powder weighs about 5 grams, so the absolute amounts of heavy metals per serving are very small. The concern is less about any single serving and more about cumulative exposure over years, especially for people who consume cocoa products daily, for children, and for pregnant women. The risk is not a reason to avoid cocoa powder entirely, but it is a reason to think of it as a flavoring agent rather than consuming it in extremely large amounts every day.
Mycotoxins in Cocoa Powder
Beyond heavy metals, cocoa powder can carry ochratoxin A (OTA), a mycotoxin produced by mold during bean fermentation and storage. A Canadian survey found OTA in 100% of 32 cocoa powder samples tested, with concentrations ranging from 0.25 to 7.8 ng/g. Six samples exceeded what was then the considered EU limit of 2 ng/g for cocoa.24PubMed Central. Ochratoxin A in cocoa and chocolate sampled in Canada An Italian survey found OTA in half of the cocoa powder samples examined, with about 29% of conventional samples above a suggested legal limit of 0.5 µg/kg. All organic samples in that study tested negative for OTA.25Food Chemistry. Ochratoxin A in Italian marketed cocoa products
A U.S. survey confirmed that OTA was detectable in all 15 natural cocoa samples and nearly all alkalized cocoa samples tested, though the mean levels (about 1.1 ng/g for both types) were relatively low.26PubMed Central. Analysis of cocoa products for ochratoxin A and aflatoxins The levels found in finished cocoa powder are well below those associated with acute toxicity in humans, and the concentrations drop substantially in final chocolate products. Still, OTA is classified as a possible human carcinogen, so chronic exposure is worth being aware of. The Italian finding that organic samples tested clean is interesting but based on a small sample size and should not be taken as a guarantee.
Cocoa and Oral Health
One counterintuitive benefit of cocoa compounds is their effect on dental bacteria. In vitro studies have shown that cocoa polyphenol pentamers significantly reduce biofilm formation and acid production by Streptococcus mutans, the primary bacterium responsible for tooth decay.27Fitoterapia. Anti-cariogenic effects of polyphenols from plant stimulant beverages (cocoa, coffee, tea) Animal studies found that cocoa extract reduced both biofilm accumulation and actual cavity development, and clinical studies reported that mouthwashes containing cocoa extract reduced S. mutans counts in saliva.28PubMed Central. Biological Properties and Antimicrobial Potential of Cocoa and Its Effects on Systemic and Oral Health This obviously does not apply if you are consuming cocoa powder loaded with sugar, but unsweetened cocoa powder on its own may actually work against the bacteria that cause cavities.
What This Means for Hershey’s Specifically
Hershey’s does not publish flavanol content on its labels, and no peer-reviewed study has tested Hershey’s cocoa in isolation for health outcomes. What we can say is that Hershey’s standard cocoa powder is natural (non-alkalized), which means it falls into the category of cocoa powders that retain the most flavanols. Hershey’s Special Dark, being Dutch-processed, would be expected to retain substantially fewer. A tablespoon of unsweetened cocoa powder of either type contains about 12 calories, 1 gram of fat, 3 grams of carbohydrate (about 2 grams of which is fiber), and 1 gram of protein. It also provides a meaningful amount of iron, magnesium, and manganese. The caloric cost of adding cocoa powder to your diet is negligible, which makes it one of the more efficient delivery vehicles for flavanols compared to, say, a chocolate bar loaded with sugar and saturated fat.
If you are choosing cocoa powder primarily for health, the evidence points toward a few practical rules: pick natural over Dutch-processed, pair it with some carbohydrate to boost flavanol absorption, do not worry about mixing it with milk, and keep your intake moderate rather than extreme to limit cumulative heavy metal exposure. One to two tablespoons a day, stirred into a smoothie, oatmeal, or warm milk, is a reasonable amount that aligns with the doses used in many of the studies showing benefit. The flavanols are genuinely active compounds with real effects on blood vessels, blood pressure, and probably the gut, but cocoa powder is not a medicine, and treating it like one by consuming it in large quantities introduces contamination risks that would not otherwise matter.