A transparent look at the decisions behind our updated SFL Kids Gummies, backed by research
At Terraseed, we don't change things lightly. Every ingredient in our products is there for a reason, and when we make a change — whether that's adding something, increasing a dose, or removing an ingredient entirely — it's because the evidence has led us there.
Our updated SFL Kids Gummies formula is the result of a thorough review of the latest pediatric nutrition research, combined with a honest look at what plant-based children actually need from a supplement — and what they don't. In this article, we want to walk you through every significant change we made, and explain exactly why we made it.
Because we believe you deserve more than a marketing claim. You deserve the science behind it.
The guiding principle: precision over quantity
Before we get into the specifics, it helps to understand the philosophy that guided this reformulation.
The supplement industry has a tendency to equate length of ingredient list with quality. More nutrients, higher percentages, bigger numbers — it all looks impressive on a label. But for children, and especially for children following a plant-based diet, what matters is not how many nutrients are in a supplement, but whether the right nutrients are present at the right doses.
Our reformulation was guided by one central question: based on the current evidence, what do vegan children genuinely need more of — and what are they likely already getting enough of through a well-planned plant-based diet?
The answers shaped every decision we made.
What we increased — and why
Zinc: from 0.6mg to 1.4mg
Of all the changes in the new formula, the increase in Zinc is perhaps the most scientifically compelling.
Zinc is critical for immune function, healthy growth, wound healing and cognitive development. In omnivore diets it is obtained primarily from shellfish and red meat. For vegan children, plant-based sources such as legumes, seeds and wholegrains do contain zinc, but also contain phytates — compounds that inhibit zinc absorption — meaning vegan kids may need significantly more dietary zinc than their omnivore peers to achieve equivalent absorption levels.
The research here is extensive and consistent. A comprehensive systematic review covering studies published between 2014 and 2025, published in the National Institutes of Health database, confirmed that zinc supplementation consistently reduced both the duration and severity of illness in children, with long-term benefits lasting for months. A separate review published by the World Health Organization found that preventive zinc supplementation reduced diarrhoea morbidity and produced statistically significant improvements in growth outcomes in children aged six months to twelve years.
Perhaps most relevant for our audience, research published in the Annals of Nutrition & Metabolism found increasing evidence that deficiency of zinc adversely affects both the physical and mental growth of children and can impair their immune defences.
Doubling our Zinc dose — from 0.6mg to 1.4mg — reflects the weight of this evidence, and the specific vulnerability of plant-based children to insufficient zinc absorption.
Vitamin C: from 6.6mg to 10mg
Vitamin C is one of the most well-researched nutrients in children's health, and the evidence for its role in immune function is robust.
The European Food Safety Authority, one of the world's most rigorous food safety bodies, has formally confirmed through scientific evaluation that Vitamin C contributes to the normal function of the immune system, specifically referencing infants and young children up to three years of age as the target population for this claim.
Beyond immunity, Vitamin C plays a particularly important role for vegan children because it significantly enhances the absorption of non-haem iron — the form of iron found in plant foods. This makes adequate Vitamin C intake doubly important for plant-based kids, who rely entirely on non-haem iron sources.
Research published jointly examining Vitamin C and Zinc found that deficiency of both nutrients together has a compounding negative effect on children's physical and mental growth and immune function. Increasing our Vitamin C dose to 10mg per gummy strengthens this combined protective effect.
Vitamin B6: from 0.37mg to 0.9mg
Vitamin B6 is an essential cofactor in the developing central nervous system, and the evidence for its importance in children's brain development is well established.
Research published in PLOS ONE confirmed that Vitamin B6 plays an essential role in brain development and functioning, with its active form being highly important in the metabolism of dopamine, serotonin, glutamate and gamma-aminobutyrate — neurotransmitters that govern mood, learning and cognitive function in children. Low B6 status has been associated with slower growth in infants and altered behavioural responses in young children.
For vegan children specifically, the bioavailability of B6 from plant sources is lower than from animal sources, meaning that even when dietary intake appears adequate, absorption may fall short. Our increase from 0.37mg to 0.9mg reflects both the central importance of this nutrient and the specific absorption challenges of a plant-based diet.
Biotin B7: from 3.3mcg to 22.5mcg
Biotin is the nutrient that supports the metabolic processes behind healthy hair, skin and nail development — all of which are in a state of rapid growth during childhood.
We want to be transparent about what the science does and does not say here. Research confirms that Biotin plays a foundational role in cellular energy production and keratin synthesis — the protein that forms the structural basis of hair and nails. The National Institutes of Health confirm that signs of biotin deficiency in children include skin rashes, hair loss and brittle nails.
However, we are also honest about the limits of the current evidence: most studies demonstrating clinical improvement from Biotin supplementation have been conducted in individuals with an underlying deficiency or pathology. What this means in practice is that our significantly increased Biotin dose is designed to ensure that no child using our formula is operating below optimal Biotin levels — supporting the normal metabolic processes that underpin healthy development, rather than making dramatic transformation claims.
For vegan children who may have lower and less consistent Biotin intake depending on their diet variety, this level of support is meaningful.
Vitamin E: from 3.3mg to 5mg
Vitamin E has long been recognised for its antioxidant properties, with a growing body of research focused on its role in protecting cells from oxidative damage during childhood development.
Vitamins E and C work synergistically — Vitamin C helps regenerate Vitamin E after it has been oxidised, meaning the two nutrients enhance each other's effectiveness when present together. Our increase in both nutrients therefore works as a complementary pair, providing broader antioxidant coverage for growing children.
Vitamin A: from 200mcg to 225mcg RAE
A modest but considered increase in Vitamin A, supporting vision development, immune function and healthy skin cell turnover — all critical during the rapid growth phases of early childhood.
What we removed — and why
Calcium, Magnesium and Niacin B3
This is arguably the most counterintuitive part of our reformulation, so we want to explain it carefully.
Removing nutrients from a children's supplement might seem like a step backwards. In fact, for most vegan children eating a reasonably varied plant-based diet, it is a step towards honesty.
Calcium, while essential for bone development, is well supplied in plant-based diets that include fortified plant milks, tofu, leafy greens like kale and pak choi, almonds and fortified cereals. The vast majority of vegan children with any dietary variety are meeting their calcium needs through food. Adding supplemental calcium on top of adequate dietary intake offers little additional benefit and simply adds to the ingredient list without adding meaningful value.
Magnesium is actually one area where a well-planned vegan diet tends to excel. It is abundant in wholegrains, legumes, nuts, seeds, dark chocolate and leafy greens — all foods that feature naturally in plant-based eating. Deficiency in vegan children eating a varied diet is relatively uncommon.
Niacin B3 is present in mushrooms, peanuts, wholegrains and fortified foods — all accessible within a plant-based diet. Unless a child has an extremely restricted diet, Niacin deficiency is rare among vegan children in developed countries.
By removing these three ingredients, we are not reducing the value of our formula. We are redirecting it — focusing our formula precisely on the nutrients where supplementation genuinely makes a difference, and trusting that a thoughtful plant-based diet is doing its job on the rest.
What we also quietly improved
Sugar: from 2.5g to 2g per gummy
We reduced the sugar content by 20% in the new formula — from 2.5g to 2g per gummy. We didn't lead with this because it's not the main story, but it matters. We know that sugar content in children's supplements is something many plant-based parents think carefully about, and we've listened.
The bottom line
Every change in this formula was driven by the same commitment: to give vegan children exactly what the evidence says they need, at doses that are appropriate for their age and their dietary context, in a product that is completely free from animal-derived ingredients.
We increased Zinc and Vitamin C because the research on their combined role in children's immune health and growth is extensive and compelling. We increased B6 because brain development matters and plant-based bioavailability is a real consideration. We increased Biotin to support healthy cellular development during the rapid growth years of childhood. We removed Calcium, Magnesium and Niacin because a well-planned vegan diet is already covering these — and we'd rather be honest about that than pad our label.
This is what science-led, values-led supplementation looks like. Not the longest ingredient list. Not the most impressive percentages. Just the right nutrients, at the right doses, for the right reasons.
References available on request. As always, we recommend discussing any supplementation with your child's healthcare provider, particularly if your child has specific dietary needs or health conditions.
Explore the full updated SFL Kids Gummies formula here.