DHA vs ARA in Baby Formula: Everything You Need to Know for Your Baby's Best Start

DHA and ARA are long-chain polyunsaturated fatty acids that make up a quarter of your baby's brain. EU law mandates every infant formula contain 20–50 mg of DHA per 100 kcal since February 2021, but the U.S. FDA treats DHA as optional. Leading European brands like HiPP, Holle, and Kendamil UK pair both nutrients at breast-milk-mimicking ratios.

Quick Answer: DHA (docosahexaenoic acid) and ARA (arachidonic acid) are long-chain polyunsaturated fatty acids found naturally in breast milk. DHA is an omega-3 essential for brain and eye development; ARA is an omega-6 essential for brain function, immune health, and growth. Since February 2021, EU law requires every infant formula sold in Europe to contain 20–50 mg of DHA per 100 kcal, a guarantee the U.S. FDA does not provide. ARA is not mandated, but every premium EU-made formula, including HiPP, Holle, and Kendamil UK, includes both, typically at an ARA-to-DHA ratio between 1:1 and 2:1 to mirror breast milk.

By the Organic Formula Shop Editorial Team   |   9 min read   |   Last updated: May 2026

DHA and ARA are the two most abundant long-chain polyunsaturated fatty acids (LCPUFAs) in the human brain, together making up roughly 25% of total brain fatty acids. Both accumulate rapidly during the third trimester of pregnancy and the first 18 months of life, the same window in which babies grow more brain mass than at any other point in their lives.

Breastfed babies receive DHA and ARA directly from their mother's milk. Formula-fed babies depend on whether, and how much, of each fatty acid the formula manufacturer adds. That single decision can shape cognitive, visual, and immune development, which is why understanding what's in the can matters.

DHA (docosahexaenoic acid) is an omega-3 fatty acid that is structurally essential for the developing brain and retina. It is naturally present in breast milk, fatty fish (such as salmon, sardines, and mackerel), and certain algae.

Infants cannot efficiently make their own DHA, the conversion rate from plant-based ALA (alpha-linolenic acid) to DHA is below 5%. For that reason, DHA in the diet, whether from breast milk or fortified formula, is the only reliable way to meet a baby's needs during the first year of life. (For the full nutrient profile of a high-quality EU infant formula, see our guide to premium European baby-formula ingredients.)

ARA (arachidonic acid) is an omega-6 fatty acid that plays a central role in brain function, immune signaling, and overall growth. It is present in breast milk, eggs, meat, and certain fungal oils such as Mortierella alpina (the standard ARA source used in European formulas).

ARA levels in human breast milk are typically equal to or higher than DHA levels, often roughly twice as high, which is why most expert bodies recommend that infant formulas contain ARA at a level at least equivalent to DHA.

Property	DHA (Omega-3)	ARA (Omega-6)
Full name	Docosahexaenoic acid	Arachidonic acid
Fatty acid family	Omega-3	Omega-6
Primary role	Brain & eye development	Brain function, immune health, and growth
Found naturally in	Breast milk, fatty fish, algae	Breast milk, eggs, meat, fungal oils
EU formula requirement	Mandatory (20–50 mg per 100 kcal)	Not mandatory, but commonly added
US formula requirement	Optional (commonly added)	Optional (commonly added)
Typical level in breast milk	~0.2–0.4% of total fatty acids	~0.35–0.7% of total fatty acids
Common source in the EU formula	Fish oil or algae oil	Mortierella alpina fungal oil

 

DHA and ARA are not interchangeable. They are complementary nutrients. DHA primarily supports neural membrane structure and visual processing, while ARA supports neural signaling, inflammatory regulation, and immune function.

Research suggests the ratio matters. A 2025 meta-analysis published in the journal Nutrients found that infants fed formula with a DHA-to-ARA ratio between 0.5 and 1 (meaning ARA at 1× to 2× the level of DHA) had significantly higher Mental Development Index scores than infants fed formula with imbalanced ratios. This finding helps explain why every leading European brand pairs DHA with ARA rather than offering DHA alone.

Yes. DHA and ARA have been added to infant formula since 2001–2002 in the United States and even earlier in parts of Europe. Decades of clinical research and post-market surveillance have established them as safe and well-tolerated at the levels used in commercial infant formula.

Both nutrients are listed on the U.S. FDA's Generally Recognized as Safe (GRAS) registry, and the European Food Safety Authority (EFSA) has affirmed their safety profile at the regulated dosage range.

On 22 February 2021, new EU regulations took effect, requiring every infant and follow-on formula sold in Europe to contain between 20 mg and 50 mg of DHA per 100 kcal, equivalent to roughly 0.5–1% of total fatty acids, which is higher than the worldwide average DHA content of breast milk.

This regulation reflects three decades of European scientific consensus that DHA is not just beneficial but essential for full-term infants. The EU treats DHA the same way it treats vitamins and trace minerals: a non-negotiable nutritional requirement.

By contrast, the U.S. FDA does not require DHA in infant formula. American manufacturers may add it voluntarily, and while most premium brands do, levels vary widely, and inclusion is not guaranteed. For a deeper comparison, see our breakdown of EU gold-standard formulas vs new U.S. brands.

Not all DHA is the same. The source matters for taste, dietary suitability, and concerns around environmental contaminants.

DHA Source	Description	Used By
Fish oil	Extracted from fatty fish (sardines, anchovies). The most common source historically.	HiPP (most lines)
Algae oil	Plant-based and vegetarian. Sourced from cultivated microalgae. Lower contaminant risk.	Kendamil UK, certain Holle products, some HiPP lines
Egg lecithin	Less common. Used in select specialty formulas.	Niche/specialty brands

 

ARA in nearly all European and American infant formulas is sourced from Mortierella alpina, a fungal oil that yields a highly purified, vegetarian-friendly form of arachidonic acid. It has been used in infant formula for over two decades with an excellent safety record.

Both sources are safe and provide the same DHA molecule. The differences come down to parental preference, dietary values, and environmental considerations.

Algae-based DHA, Best for Vegetarian Families and Allergy Concerns Strengths •       Plant-based and suitable for vegetarian families •       Lower risk of heavy-metal and ocean-contaminant exposure •       Sustainable, lab-cultivated, and free from fishing-industry impact •       No fishy aftertaste, generally better-tolerated palate Best for: Vegetarian households, parents with fish allergies, or families prioritizing sustainability. Found in Kendamil UK, select Holle lines, and an increasing share of HiPP products. (See our Kendamil vs HiPP comparison for a side-by-side breakdown.)

 

Fish-oil-based DHA, Traditional Source with Long Clinical Track Record Strengths •       Decades of clinical research support •       Tends to be more cost-effective •       EU-sourced fish oils are tightly regulated for purity •       Naturally also provides small amounts of EPA Best for: Parents who prefer the most-studied DHA source and have no dietary or sustainability concerns. Found in most HiPP lines and many traditional European formulas.

 

Use this checklist when comparing labels:

•       Confirm DHA is present. Every EU-made infant formula will list DHA; that's a regulatory minimum. If you're considering a U.S. formula, check the ingredient panel directly.

•       Look for ARA alongside DHA. Reputable premium brands include both. ARA should ideally be at a level equal to or higher than DHA, reflecting breast-milk ratios.

•       Check the source. If you prefer plant-based, look for algae-derived DHA (Schizochytrium or Crypthecodinium oil) and ARA from Mortierella alpina.

•       Verify the stage matches your baby's age. DHA and ARA needs evolve; Stage 1 formulas typically have a higher LCPUFA density relative to caloric intake than Stage 3 formulas. Our HiPP Dutch stage guide walks through the full progression from 0–24+ months.

•       Choose a trusted retailer. Formula freshness directly affects fatty-acid stability. Buy from importers that ship directly from temperature-controlled European warehouses.

Here is a quick overview of how the leading European brands handle DHA and ARA across their core product lines:

Brand	DHA Source	ARA Included	Notable
HiPP	Fish oil (most lines)	Yes	Adds prebiotics (GOS) and probiotics
Holle	Fish oil or algae (varies)	Yes	Demeter-certified biodynamic farming
Kendamil UK	Algae oil (plant-based)	Yes	No fish oil, no palm oil; whole-milk recipe

 

Formula Fact: A baby's brain triples in size during the first year of life. DHA and ARA together account for roughly a quarter of the brain's fatty-acid content, making the right LCPUFA blend in formula one of the most consequential ingredient decisions a parent makes during the first 12 months.

 

Is DHA required in U.S. baby formula?

No. DHA is optional in U.S. infant formula under FDA regulations. Most premium American brands add it voluntarily, but the amount and source can vary. Every EU-made formula, by contrast, must contain 20–50 mg of DHA per 100 kcal.

Is ARA required in European baby formula?

No, ARA is not mandated by EU regulations. Still, virtually every premium EU-made brand, including HiPP, Holle, and Kendamil UK, includes ARA alongside DHA because clinical evidence supports the combination for balanced brain development.

Is algae-based DHA as good as fish-based DHA?

Yes. The DHA molecule is identical regardless of source. Algae-based DHA offers advantages for vegetarian families, parents with fish allergies, and those concerned about ocean contaminants. Fish-based DHA has a longer clinical research track record.

Can my baby get DHA from breast milk alone?

Yes, provided the breastfeeding parent consumes enough DHA themselves. DHA in breast milk reflects the parent's dietary intake. For non-breastfeeding parents, a DHA-fortified formula ensures their baby receives the required amount, regardless of their diet.

What is the ideal DHA-to-ARA ratio in formula?

Most international expert groups recommend that ARA be present at a level equal to or higher than DHA, reflecting breast-milk ratios. A 2025 meta-analysis suggested that a DHA/ARA ratio between 0.5 and 1 (i.e., ARA at 1×–2× DHA) is associated with better infant cognitive outcomes.

Are there any side effects from DHA or ARA in the formula?

No serious side effects have been linked to DHA or ARA at regulated levels. Both are recognized as safe by the FDA, EFSA, and the World Health Organization. If you observe digestive intolerance, it is almost always related to other ingredients (such as a protein source) rather than DHA or ARA.

DHA (Docosahexaenoic acid): An omega-3 fatty acid essential for infant brain and eye development. Mandatory in the EU infant formula since 2021.

ARA (Arachidonic acid): An omega-6 fatty acid essential for brain function, immune health, and growth. Naturally abundant in breast milk.

LCPUFA: Long-chain polyunsaturated fatty acids; the family of fatty acids that includes DHA and ARA.

ALA (Alpha-linolenic acid): A plant-based omega-3 fatty acid that the body can convert, inefficiently, to DHA.

EPA (Eicosapentaenoic acid): Another omega-3 fatty acid found in fish oil. Often present in small amounts alongside DHA.

Mortierella alpina: A naturally occurring soil fungus cultivated to produce the ARA used in nearly all premium infant formulas.

Schizochytrium / Crypthecodinium: Marine microalgae cultivated to produce plant-based DHA for vegetarian formulas.

EFSA: The European Food Safety Authority, the EU body that sets and enforces infant formula composition standards.

FDA: The U.S. Food and Drug Administration regulates infant formula in the United States.

GRAS: Generally Recognized as Safe; the FDA classification confirming the safety of an ingredient such as DHA or ARA.

DHA and ARA are foundational nutrients for the first 18 months of your baby's life. They are not optional extras; they are core building blocks of the developing brain, retina, and immune system.

Europe requires DHA in every infant formula. The U.S. FDA does not. That single regulatory difference is why EU-made formulas remain the gold standard for parents who want a guaranteed DHA floor. The leading EU-made brands voluntarily pair DHA with ARA at breast-milk-mimicking ratios. Whether you choose a fish-oil-based formula from HiPP, a biodynamic option from Holle, or an algae-based formula from Kendamil UK, all three give your baby a DHA and ARA profile that closely reflects what nature intended: the composition of breast milk itself.

U.S. formulas can certainly meet your baby's basic needs, but EU-made formulas are held to a measurably higher standard. Combine that ingredient quality with a reputable retailer that ships fresh, authentic European product directly to your door, and you can feed with the same confidence parents across Europe have relied on for generations. Ready to pick a brand? Start with our 2026 Buyer's Guide to the Best European Organic Baby Formula.

Contact

Contact our dedicated customer support team for expert advice and guidance tailored to your baby's needs. They have earned hundreds of 5-star reviews from our customers, helping you to provide the best nutrition for your little one. Contact us here or email us at support@organicformulashop.com. We're here to help! 

Disclaimer: This article is for informational purposes only and is not intended as medical advice. Always consult your pediatrician or healthcare professional before making changes to your baby's diet or nutrition.