Hazelnut Health Benefits: PAC 501 mg, MnSOD, and More
Hazelnut articles say they're high in antioxidants and good for your heart. What they don't tell you: hazelnuts contain 501 mg of proanthocyanidins (PAC) per 100 grams, the highest of any common tree nut, ahead of pecans at 494 mg. Brazil nuts, macadamias, and pine nuts contain zero. A meta-analysis of 9 hazelnut-specific trials found significant LDL reduction of -0.150 mmol/L. Hazelnuts provide 87% DV of manganese per ounce, the cofactor for MnSOD, the primary antioxidant enzyme inside the mitochondria. The brown skin contains 168 to 489 times more phenolic compounds than the kernel beneath it. And hazelnuts were in the PREDIMED trial nuts arm that showed 28% lower relative cardiovascular event risk. None of that is on any competitor page. This one covers it.
- Hazelnuts have the highest proanthocyanidin (PAC) content of any common tree nut at 501 mg per 100g, a compound class completely absent from Brazil nuts, macadamias, and pine nuts
- One ounce provides 87% DV manganese, the highest of any tree nut, which is the cofactor for MnSOD, the only antioxidant enzyme that protects your mitochondria from superoxide damage
- A 9-study meta-analysis covering 425 participants found hazelnuts reduced LDL by -0.150 mmol/L without affecting HDL
- The brown skin contains 168 to 489 times more phenolic compounds than the white kernel, making skin-on raw hazelnuts meaningfully different from blanched or heavily roasted
- At 2g net carbs per oz, hazelnuts fit low-carb and keto diets, and pair with cashews and Brazil nuts to cover all three major cellular antioxidant enzyme systems
Why Hazelnut Health Benefits Stand Apart from Other Tree Nuts
Most tree nut comparisons focus on a single lead nutrient: almonds lead on vitamin E, walnuts on ALA, Brazil nuts on selenium, pistachios on DIAAS protein, cashews on copper. Hazelnuts have two things that set them apart and that get almost no coverage in mainstream nutrition writing: the highest proanthocyanidin content of any common tree nut, and the most extreme skin-to-kernel polyphenol concentration ratio in the nut family.
One ounce of hazelnuts (about 20 whole kernels) provides 178 calories, 17 grams of fat (predominantly oleic acid MUFA), 4 grams of protein, 3 grams of fiber, 2 grams of net carbs, 87% DV manganese, 24% DV copper, 21% DV vitamin E, and 12% DV thiamine. Turkey produces approximately 62 to 70% of the global hazelnut supply. Oregon grows 99% of US commercial hazelnuts, and Oregon hazelnuts are generally larger and more consistent in flavor than Turkish varieties. Oregon supplies the premium confectionery and fresh snacking market; Turkey dominates industrial chocolate and hazelnut paste production.
What Proanthocyanidins Are and Why They Drive Hazelnut Health Benefits
Understanding hazelnut health benefits starts with proanthocyanidins (PAC), also called condensed tannins or oligomeric proanthocyanidins, are polyphenol compounds built from chains of flavan-3-ol units, primarily catechin and epicatechin. They're the compounds that make red wine, dark chocolate, and green tea astringent. In hazelnuts, they're present at 501 mg per 100 grams, based on the USDA PAC database, the most detailed measurement of these compounds across food groups.
No other common tree nut comes close. Pecans are second at 494 mg per 100g. Almonds, walnuts, and pistachios contain PAC but at substantially lower concentrations. Brazil nuts, macadamias, and pine nuts contain no measurable PAC at all. This is not a minor nutritional difference. It means hazelnuts deliver a polyphenol compound class that is either absent or much less concentrated in most other nuts in the typical daily rotation.
The biological activity of hazelnut PAC is well-documented. They inhibit platelet aggregation, reduce LDL oxidative susceptibility, suppress NF-kB and pro-inflammatory cytokines, and have demonstrated dose-dependent effects in cancer cell research. Human trial data includes the cardiovascular meta-analysis and the DNA damage RCT, both of which provide direct in-vivo evidence of biological activity.
PAC content and processing: PAC content drops with roasting and skin removal. The majority of hazelnut PAC are concentrated in the brown skin. Roasting decreases PAC content as heat degrades some of the more polymerized PAC chains. Blanching, which removes the skin entirely, eliminates most PAC along with the phenolic acids, flavonols, and other polyphenols concentrated in the skin. For maximum PAC content, raw skin-on hazelnuts are the form to use.
The Hazelnut LDL Meta-Analysis and the PREDIMED Nuts Arm
This is the most specific hazelnut cardiovascular evidence available, covering only hazelnut trials rather than mixed nut data. The pooled analysis found significant LDL reduction of -0.150 mmol/L (95% highest posterior density interval: -0.308 to -0.003). Total cholesterol showed a trend toward decrease at -0.127 mmol/L, which was not significant but directionally consistent. HDL cholesterol remained substantially stable (pooled change: +0.002 mmol/L), meaning hazelnuts lowered LDL without reducing HDL. This is the favorable lipid profile change. Triglycerides and BMI were unchanged.
The dose range of 29 to 69 grams per day in the included trials covers 1 to 2.5 ounces. The lower end of this range, approximately 30g (around 20 whole hazelnuts), is consistent with the PREDIMED mixed-nut daily serving recommendation and is the most practical daily target for sustained habit formation.
Hazelnuts in the PREDIMED Trial Nuts Arm
The PREDIMED trial (Prevención con Dieta Mediterránea) is one of the largest dietary intervention trials ever conducted, enrolling over 7,447 participants at high cardiovascular risk for an average of nearly 5 years. It compared three interventions: Mediterranean diet supplemented with extra-virgin olive oil, Mediterranean diet supplemented with mixed nuts (30g per day of walnuts, almonds, and hazelnuts in a 15:7.5:7.5g ratio), and a low-fat control diet.
The nuts arm found a 28% lower relative risk of cardiovascular events compared to the control diet (hazard ratio 0.72, 95% CI 0.54 to 0.96), with particularly strong effects on stroke reduction. Hazelnuts contributed one-quarter of the daily nut dose in this arm. While PREDIMED reflects the combined effect of walnuts, almonds, and hazelnuts together, hazelnuts' specific PAC content, oleic acid profile, and polyphenol density contributed distinct mechanisms that almonds and walnuts don't replicate. PREDIMED is the strongest long-term human evidence for hazelnut-containing nut mixtures on cardiovascular outcomes. For the walnut-specific mechanisms in the same PREDIMED nuts arm, see Walnut Health Benefits: What 50 Years of Research Shows.
Manganese 87% DV and the MnSOD Mitochondrial Antioxidant Mechanism
Hazelnuts provide 0.618 mg of manganese per ounce, equivalent to 87% of the adult daily value from a single 20-kernel serving. No other common tree nut comes close. For comparison: cashews provide around 40% DV, almonds 27% DV, walnuts 28% DV. Pecans are strong at 38% DV, but hazelnuts lead by a significant margin.
The biological significance of this concentration is specific. Manganese is the cofactor for MnSOD, manganese superoxide dismutase, the primary antioxidant enzyme inside the mitochondria. This is distinct from Cu-Zn SOD (copper-zinc, cytoplasmic, from cashews) and GPx (glutathione peroxidase, selenium-dependent, from Brazil nuts). MnSOD sits specifically in the mitochondrial matrix, where it is needed most.
Why MnSOD and the Mitochondria Matter
Mitochondria generate ATP through oxidative phosphorylation. As an unavoidable byproduct of this energy production, electrons leak from the electron transport chain and react with oxygen to form superoxide radicals. Superoxide readily converts to hydrogen peroxide and hydroxyl radicals, which are highly reactive. Left unchecked, mitochondrial superoxide damages mitochondrial DNA, oxidizes the membrane lipids of the mitochondrial inner membrane, and impairs the electron transport chain complexes themselves. This creates a feedback loop: damaged mitochondria generate more superoxide, which causes more damage.
MnSOD is the first responder to this mitochondrial superoxide. It dismutates two superoxide radicals into one hydrogen peroxide and one oxygen molecule. The hydrogen peroxide is then handled by mitochondria-specific GPx. Hazelnuts at 87% DV manganese per ounce are the most efficient whole-food source for meeting this requirement among all tree nuts. For how the selenium-GPx mechanism complements hazelnut MnSOD, see How Many Brazil Nuts Per Day for Selenium?.
Why the Hazelnut Skin Matters More Than Any Other Part
The relationship between the hazelnut skin and the kernel is more extreme than any other nut. Studies measuring phenolic compound content across hazelnut varieties consistently find the skin contains 168 to 489 times more total phenolic compounds than the kernel. The specific range depends on cultivar and growing conditions, but the direction is unambiguous: essentially all of the hazelnut's polyphenol content is in the thin brown skin, not the white kernel.
The phenolics concentrated in the skin include gallic acid, epicatechin, catechin, quercetin, kaempferol, myricetin, procyanidins, and caffeic acid derivatives. These compounds have direct antioxidant capacity, reduce LDL oxidation, inhibit pro-inflammatory signaling through NF-kB, and support endothelial function. The kernel contains the fats, protein, vitamin E, and minerals, but contributes minimally to hazelnut's polyphenol activity.
Skin-on hazelnut consumption reduced endogenous DNA damage by 18.9% (p=0.002) and oxidatively induced DNA strand breaks by 16% (p=0.02). The skin-removed condition showed similar but quantitatively smaller effects, suggesting the skin polyphenols add meaningful antioxidant protection beyond what the kernel alone provides. This is one of the clearest direct demonstrations of skin-on versus skin-off making a clinical difference in nut research. The DNA damage reduction mechanisms apply to all dividing cells, not only those in the cardiovascular system.
Hazelnuts and Folate: Why They're the Highest Tree Nut Source
Hazelnuts contain more folate (vitamin B9) than any other common tree nut, at approximately 8% DV per ounce. This matters in two specific contexts.
First, folate is required for the remethylation of homocysteine to methionine via the methionine synthase reaction. Adequate folate keeps homocysteine levels low. Elevated homocysteine is an independent cardiovascular risk marker, associated with endothelial dysfunction and increased thrombosis risk. For people with the MTHFR gene variant that reduces folate processing efficiency (found in approximately 40 to 60% of the population), dietary folate from a variety of food sources including hazelnuts is particularly valuable.
Second, a 2019 ISGlobal cohort study (INMA birth cohort) found that children of mothers who ate nuts regularly during pregnancy, including hazelnuts, had significantly better neuropsychological development scores at ages 18 months and 5 and 8 years. The researchers attributed benefits partly to folate and partly to essential fatty acids that accumulate in neural tissue. Hazelnuts' folate content contributed to this effect in the nuts group that included both hazelnuts and walnuts.
Hazelnut Health Benefits: Full Nutrition Profile Per Ounce
| Nutrient / Compound | Per 1 oz (28g) | Primary Mechanism | Key Evidence |
|---|---|---|---|
| Proanthocyanidins (PAC) | 501 mg/100g (#1 tree nut) | LDL oxidation inhibition; platelet aggregation suppression; NF-kB anti-inflammatory pathway inhibition | Meta-analysis: LDL -0.150 mmol/L. DNA damage RCT: endogenous damage -18.9%. Zero PAC in Brazil nuts, macadamias, pine nuts |
| Manganese (for MnSOD) | 87% DV (0.618 mg) highest tree nut | MnSOD cofactor: mitochondrial superoxide dismutation. First line of defense against respiration-generated ROS. Distinct from Cu-Zn SOD and GPx | MnSOD deficiency associated with mitochondrial dysfunction and accelerated aging in animal models. Hazelnuts are the most efficient tree nut source for MnSOD support |
| Skin polyphenols | 168 to 489x the kernel concentration | Epicatechin, catechin, quercetin, kaempferol, gallic acid, procyanidins: antioxidant, anti-inflammatory, endothelial support | Skin-on vs skin-off RCT: DNA damage difference confirmed. Blanching removes essentially the entire polyphenol payload |
| Vitamin E (alpha-T) | 21% DV | LDL oxidation protection in circulation; cell membrane antioxidant. Synergistic with PAC on LDL oxidation | 8-week hypercholesterolemia study: oxidative stress decreased significantly |
| Oleic acid (MUFA) | 12.9g (~76% of total fat) | Displaces saturated fat; LDL particle oleic acid reduces oxidative susceptibility; endothelial health. MUFA profile similar to olive oil | PREDIMED nuts arm benefit partly attributed to nut MUFA content |
| Folate (B9) | 8% DV highest tree nut | Homocysteine remethylation to methionine; neural tube development; neurotransmitter synthesis | ISGlobal INMA cohort: nut consumption (including hazelnuts) linked to better neuropsychological development scores at 1.5, 5, and 8 years |
| Copper | 24% DV | Ceruloplasmin (ferroxidase); Cu-Zn SOD (with zinc). Second highest copper after cashews (69% DV) | Supports LDL protection via ceruloplasmin alongside cashews' higher copper contribution |
| Thiamine (B1) | 12% DV | Pyruvate dehydrogenase cofactor; acetylcholine synthesis; myelin maintenance; energy metabolism | Strong thiamine source across tree nuts. Neurological function and energy metabolism |
| Net carbs | 2g per oz | Low glycemic impact; keto-compatible alongside macadamias (1.5g) and pecans (1.1g) | Suitable for low-carb diets, PCOS management, and blood sugar-sensitive individuals |
| Fiber | 3g | Prebiotic; colonocyte fuel via butyrate from gut fermentation; LDL-C lowering via bile acid sequestration | In vitro fiber study: hazelnut fiber promotes Lachnospiraceae and Ruminococcaceae gut bacteria, consistent with metabolic health benefit |
How Hazelnut Health Benefits Complete the Full Antioxidant Enzyme Rotation
One of the most useful ways to think about a daily nut rotation is by which antioxidant enzyme system each nut primarily supports. Three distinct enzymatic systems protect cells from oxidative damage, and they require different mineral cofactors from completely different nuts.
- GPx (glutathione peroxidase): neutralizes hydrogen peroxide and lipid peroxides. Cofactor: selenium, highest in Brazil nuts (68 to 91 mcg per nut). See Brazil Nuts Health Benefits: Selenium Science and Research
- Cu-Zn SOD (copper-zinc superoxide dismutase): neutralizes cytoplasmic superoxide radicals. Cofactors: copper and zinc, highest in cashews (69% DV copper per oz). See Cashew Health Benefits: ApoB, Copper-Ceruloplasmin, and More
- MnSOD (manganese superoxide dismutase): neutralizes mitochondrial superoxide radicals. Cofactor: manganese, highest in hazelnuts (87% DV per oz)
These three enzymes work sequentially: MnSOD converts mitochondrial superoxide to H2O2; Cu-Zn SOD handles cytoplasmic superoxide; GPx neutralizes the H2O2 both produce. Eating hazelnuts, cashews, and Brazil nuts on the same day provides cofactor support for all three enzyme steps. For the complete energy and mineral rotation across all nuts, see What Nuts Give You the Most Energy? Ranked by Mechanism.
How Many Hazelnuts Per Day for Maximum Hazelnut Health Benefits?
The clinical research provides a practical daily range for hazelnut health benefits. The meta-analysis pooled hazelnut trials using 29 to 69 grams per day (approximately 1 to 2.5 oz). The PREDIMED nuts arm used 7.5g of hazelnuts per day as part of the 30g total mixed nut dose.
| Goal | Daily Amount | Research Basis | Notes |
|---|---|---|---|
| LDL reduction | 1 to 2.5 oz (29 to 69g) | 9-study meta-analysis dose range | LDL -0.150 mmol/L across full dose range. Lower doses (1 oz) more practical for daily sustained habit |
| PREDIMED protocol | 7.5g hazelnuts as part of 30g mixed nuts | PREDIMED nuts arm: CVD -28% | Combined with walnuts and almonds. Full 30g total nut dose is what produced the cardiovascular outcome |
| MnSOD manganese support | 1 oz (87% DV manganese) | Daily adequate intake via food | One ounce covers nearly the full daily manganese requirement for MnSOD cofactor support |
| PAC and skin polyphenols | 1 oz or more, skin-on | DNA damage RCT (skin-on form) | PAC delivery requires raw skin-on hazelnuts. Blanched hazelnuts lose this fraction entirely |
| General daily snacking | 1 to 1.5 oz (20 to 30 kernels) | Multiple trials, practical range | 178 calories per oz, 2g net carbs, 3g fiber. Moderately keto-compatible at one ounce servings |
Keto and low-carb compatibility: At 2g net carbs per ounce (5g total carbs minus 3g fiber), hazelnuts are moderately keto-compatible alongside macadamias (1.5g net carbs) and pecans (1.1g net carbs). One to 1.5 oz per day contributes 2 to 3g net carbs, fitting within a 20 to 25g daily target. Their 76% MUFA fat profile makes them one of the most olive-oil-equivalent nuts for fat quality. For the full low-carb nut comparison, see Macadamia Nuts Health Benefits.
Raw vs Roasted Hazelnuts: What the Difference Means for Health Benefits
Unlike some nuts where raw versus roasted differences are minimal, the distinction matters significantly for hazelnuts because of where the health-active compounds are located.
| Factor | Raw Skin-On | Lightly Roasted Skin-On | Blanched (Skin Removed) |
|---|---|---|---|
| PAC (proanthocyanidins) | Full 501 mg/100g | Partially reduced (heat degrades polymerized PAC chains) | Essentially eliminated (skin removed) |
| Skin polyphenols (catechin, quercetin, kaempferol) | Full concentration | Partially retained | Removed entirely with skin |
| Manganese (MnSOD cofactor) | 87% DV per oz | Essentially unchanged | Essentially unchanged (mineral) |
| Vitamin E (alpha-tocopherol) | 21% DV per oz | Small reduction at high heat | Kernel E retained; skin polyphenols lost |
| Flavor | Mild, earthy, slightly sweet | Richer, deeper, more satisfying for snacking | Mild and clean; preferred for hazelnut spreads and flour |
| Best for | Maximum hazelnut health benefits (all PAC and skin polyphenols intact) | Daily snacking compliance while retaining most benefits | Hazelnut butter, flour, chocolate spreads, Italian pastry |
Hazelnut Health Benefits for Skin and Hair
Several key hazelnut health benefits for skin and hair come from the same nutrients that support cardiovascular and mitochondrial health. The mechanisms overlap more than most people expect.
Alpha-Tocopherol and Skin Aging
Hazelnuts provide 21% DV vitamin E per ounce as alpha-tocopherol. The sebaceous glands near skin follicles secrete alpha-tocopherol into the skin surface lipids, where it reinforces the skin's antioxidant barrier against photo-oxidation from UV exposure. This is the same mechanism that makes vitamin E supplementation effective for reducing skin lipid peroxidation and visible signs of photoaging. Alpha-tocopherol also protects LDL particles in circulation from oxidation, and these two mechanisms, cardiovascular and dermal, are driven by the same compound at the same dose.
PAC and Collagen Protection
The PAC and phenolic compounds in hazelnut skin inhibit matrix metalloproteinases (MMPs), the enzymes that break down collagen in skin tissue. MMP activity increases with UV exposure and inflammation, and is the primary molecular driver of fine lines and loss of skin elasticity. The NF-kB inhibition by hazelnut PAC reduces the inflammatory signaling that upregulates MMPs. This is a documented mechanism in polyphenol research, and hazelnut's PAC at 501 mg per 100g makes them one of the stronger whole-food sources for this pathway. For the full antioxidant skin health comparison across nuts, see Best Snack Nuts for Antioxidants and Skin Health.
Copper for Hair Growth and Pigmentation
Hazelnuts provide 24% DV copper per ounce. Copper activates tyrosinase, the enzyme required for melanin synthesis in hair follicles. Melanin gives hair its color, and copper deficiency is associated with premature graying via reduced tyrosinase activity. Copper also activates lysyl oxidase, which crosslinks collagen and elastin in the scalp's extracellular matrix, supporting healthy follicle structure. For women specifically, the copper-hair connection is one of the most practical hazelnut micronutrient benefits to consider alongside manganese's role in hormonal regulation. For the complete picture of pecan, hazelnut, and nut benefits for women, see Pecan Benefits for Female Health: PMS, Heart, Bones, and More.
Hazelnut Health Benefits vs Other Tree Nuts: Where Hazelnuts Lead
| Nut | Where It Leads | Where Hazelnuts Are Stronger |
|---|---|---|
| Hazelnuts | PAC (#1, 501 mg/100g), manganese (87% DV), folate (#1), MnSOD cofactor, skin polyphenols | N/A this is the benchmark row |
| Almonds | Vitamin E (49% DV), fiber (3.5g), ApoB 36-RCT meta-analysis, phytosterols | Hazelnuts lead on PAC, manganese, folate, skin polyphenol concentration |
| Walnuts | ALA omega-3 (2.5g), WAHA 2-year trial, ellagitannins, gamma-tocopherol COX-2 | Hazelnuts lead on PAC, manganese, folate, MUFA dominance |
| Cashews | Copper (69% DV, highest tree nut), iron (1.8mg), Cu-Zn SOD, ApoB RCT | Hazelnuts lead on PAC, manganese, folate, skin polyphenols |
| Pecans | ORAC #1 (17,940 units/100g), gamma-tocopherol, dual COX-2 inhibition, LP-IR | Hazelnuts lead on PAC (501 vs 494 mg), manganese, folate. Pecans lead on overall antioxidant capacity score |
| Pistachios | DIAAS 86 protein quality, lutein, melatonin, NMA #1 LDL/TC/TG, B6 | Hazelnuts lead on PAC, manganese, folate, MUFA |
| Brazil nuts | Selenium (68-91 mcg per nut), 25 selenoproteins, GPx | Hazelnuts lead on PAC, manganese, folate, fat quality. Zero PAC in Brazil nuts |
For the complete pecan antioxidant picture that pairs with hazelnut PAC, see Pecans Health Benefits: What the Research Shows. For the almond ApoB meta-analysis that complements hazelnut LDL data, see Almond Health Benefits: 36-Trial Meta-Analysis and Mechanisms.
How to Store Raw Hazelnuts for Maximum Freshness and Nutrition
Hazelnut MUFA (76% of total fat) is more oxidatively stable than PUFA-heavy nuts like walnuts, but the skin polyphenols that drive the PAC and DNA damage findings are sensitive to heat, air, and light over time. Rancid hazelnuts develop a bitter, sharp taste that is immediately obvious. Freshness is a functional quality issue for hazelnuts, not just a flavor preference.
- Pantry, sealed bag, cool dark location: 6 to 9 months for raw skin-on hazelnuts. The skin acts as a natural barrier against oxidation. Seal firmly after every use
- Refrigerator, airtight container or sealed bag: Up to 12 months. Recommended for any bag you will take longer than 3 months to finish, especially in warm kitchens
- Freezer, airtight container: Up to 2 years with no change in texture or flavor. For 3 lb or 5 lb bags, freeze half on arrival and pull to the pantry as needed
Freshness test: Fresh raw hazelnuts smell clean, mildly sweet, and distinctly nutty with an earthy undertone. Rancid hazelnuts smell sharp, bitter, or musty. Any batch with this odor should be discarded regardless of the labeled date. Browse the full hazelnuts collection for available sizes from 0.25 lb sampler to 5 lb bulk.
What Customers Say About Nut Cravings Hazelnuts
Best raw hazelnuts found anywhere. The skin is intact as expected and the flavor is rich, earthy, and distinctly hazelnut with no staleness. Specifically wanted skin-on because of the polyphenol content being in the skin. OU Kosher, resealable bag, consistent freshness across every order. Also buys almonds and cashews from Nut Cravings. Excellent quality across the board.
Excellent raw hazelnuts. Large Oregon-grown kernels with the skin intact, great flavor, fresh and clean. Uses them in homemade hazelnut butter and for baking. OU Kosher certification is important for his household. Resealable bag keeps them fresh. Fast shipping and consistently high quality every time. Nut Cravings is his go-to for all nuts.
Has been ordering hazelnuts from Nut Cravings for about three months with quality exceptional every time. Clearly Oregon-grown premium hazelnuts with the skin intact, which matters enormously since practically all the polyphenols are in the skin. Flavor is rich, distinctly nutty, slightly sweet, with that characteristic hazelnut earthiness that good fresh hazelnuts have and stale ones don't. Specifically buys raw skin-on because she makes her own hazelnut butter and uses them in baking. OU Kosher certification gives complete confidence in the sourcing. Also regularly orders almonds, cashews, and walnut halves. The Good Morning America feature is what first brought her to Nut Cravings and the product quality has kept her coming back every month.
Frequently Asked Questions: Hazelnut Health Benefits
Q: What are the health benefits of hazelnuts?
Four distinct advantages backed by clinical research: (1) 501 mg PAC per 100g, highest of any tree nut, with zero PAC in Brazil nuts, macadamias, and pine nuts; (2) 87% DV manganese per oz, highest tree nut, cofactor for MnSOD mitochondrial antioxidant enzyme; (3) LDL -0.150 mmol/L from 9-study 425-participant meta-analysis with HDL unchanged; (4) PREDIMED nuts arm, CVD -28% hazard ratio 0.72. The skin contains 168 to 489 times more polyphenols than the kernel. Browse all hazelnuts at Nut Cravings.
Q: How many hazelnuts should you eat per day?
One to 1.5 oz per day (20 to 30 kernels) is the practical daily range. The 9-study meta-analysis used 29 to 69g per day (1 to 2.5 oz). The PREDIMED protocol used 7.5g hazelnuts as part of a 30g total mixed nut dose. One oz provides 178 calories, 87% DV manganese, 21% DV vitamin E, 24% DV copper, 3g fiber, and 2g net carbs. Shop Raw Hazelnuts With Skin here.
Q: Are raw hazelnuts better than roasted?
Yes for PAC and skin polyphenols specifically. Raw skin-on hazelnuts preserve the full 501 mg/100g PAC and the 168 to 489x skin polyphenol concentration that drove the DNA damage RCT results. Roasting degrades some polymerized PAC chains. Blanching removes the skin and eliminates most of the polyphenol fraction entirely. Manganese, copper, and vitamin E content are essentially unchanged by roasting. For the antioxidant skin and hair comparison across nuts, see Best Snack Nuts for Antioxidants and Skin Health.
Q: Do hazelnuts lower cholesterol?
Yes. A Bayesian meta-analysis of 9 hazelnut-specific RCTs (425 participants, 29 to 69g per day) found LDL -0.150 mmol/L with HDL unchanged, total cholesterol trending -0.127 mmol/L, and no effect on TG or BMI. Three mechanisms: phytosterols block NPC1L1 cholesterol absorption, oleic acid (76% of fat) improves LDL particle quality, and PAC inhibit LDL oxidation. PREDIMED nuts arm (including hazelnuts): CVD -28% vs control. For the walnut comparison within the same PREDIMED trial, see Walnut Health Benefits: What 50 Years of Research Shows.
Q: Are hazelnuts good for skin and hair?
Yes through three pathways: (1) 21% DV alpha-tocopherol vitamin E per oz protects skin surface lipids from photo-oxidation and collagen from LDL-linked oxidative damage; (2) PAC and skin polyphenols inhibit matrix metalloproteinases (MMPs) that break down collagen, reducing the molecular driver of fine lines and elasticity loss; (3) 24% DV copper per oz activates tyrosinase for melanin hair pigmentation and lysyl oxidase for collagen and elastin crosslinking in scalp tissue. For the full picture of hazelnuts in women's health, see Pecan Benefits for Female Health: PMS, Heart, Bones, and More.
Shop Raw Hazelnuts at Nut Cravings
Oregon-grown, skin-on, unsalted. OU Kosher certified. Packed fresh Monroe, NY. Free shipping on orders over $25.