Supplement and sports nutrition stores typically have very high variant counts (every flavour × every size = a separate SKU) and strict regulatory requirements around what can be said about a product. Getting the variant structure right and separating compliant health claims from marketing copy is essential work before migrating to Shopify.

Supplement and nutrition product categories

Protein powders: Whey concentrate, isolate, casein, vegan blends, collagen. Flavour and size variants. Key specs: protein per serving, calorie count.
Pre-workout and energy: High-caffeine, non-stim, pump formulas. Flavour variants. Caffeine content metafield important for safety.
Vitamins and minerals: Individual vitamins (D3, C, B12, zinc) and multi-vitamin blends. Dose per capsule, capsule count variants.
Amino acids: BCAAs, glutamine, creatine (unflavoured and flavoured). Serving size and format (powder/capsule) variants.
Weight management: Fat burners, meal replacements, appetite control. Subject to stricter health claim rules.
Herbal and botanical: Ashwagandha, turmeric, lion's mane. Standardised extract percentage metafield.
Food and snacks: Protein bars, quest bars, healthier snacks. Box/case vs individual variants.
Sports performance: Electrolytes, recovery, joint support, omega-3.

Flavour × size variant matrix

Protein and pre-workout products commonly come in 5–8 flavours × 3 sizes (250g trial / 1kg / 5kg). That's up to 24 variants per product — well within Shopify's 100-variant limit — but managing it cleanly is important.

In WooCommerce, these are stored as pa_flavour and pa_size attributes. In Shopify:

Option 1: Flavour → "Chocolate Fudge / Vanilla / Strawberry Milkshake / Unflavoured"
Option 2: Size → "250g / 1kg / 2kg / 5kg"

Each flavour × size combination is a distinct variant with its own SKU, price, and inventory. k-sync maps the WooCommerce attribute pairs to Shopify option combinations automatically. Verify that all SKU combinations exist in WooCommerce — missing combinations (e.g., no 5kg trial size for newer flavours) should have available = false variants created in Shopify, not omitted entirely.

Product metafields for supplements

Metafield	Example	Use
nutrition.serving_size_g	30 / 25 / 5	Per-serving info
nutrition.servings_per_container	33 / 67 / 166	Value calculation
nutrition.protein_per_serving_g	24 / 22 / 20	Key buying metric
nutrition.calories_per_serving	120 / 140 / 105	Diet-conscious filter
nutrition.caffeine_per_serving_mg	200 / 150 / 0	Safety + filter
nutrition.format	Powder / Capsule / Tablet / Liquid / Bar	Type filter
nutrition.suitable_for_vegetarian	true / false	Diet filter
nutrition.suitable_for_vegan	true / false	Diet filter
nutrition.gluten_free	true / false	Allergen filter
nutrition.allergens	Milk,Soy / None	EU allergen list
nutrition.informed_sport_certified	true / false	Anti-doping badge
nutrition.batch_tested	true / false	Quality badge
nutrition.country_of_manufacture	UK / USA / Germany	Trust signal
nutrition.best_before_shelf_life_months	24 / 30	Perishable products

UK food supplement regulations and health claims

UK food supplement law (the Food Supplements (England) Regulations 2003, and corresponding devolved legislation) and the UK retained version of EU Regulation 1924/2006 restrict what health claims can be made about food supplements.

Permitted claims are listed in the GB NHC Register. Prohibited claims include:

"Treats", "cures", or "prevents" any disease or condition
Claims not on the approved register
Implied medicinal claims through product naming

During migration, review WooCommerce product descriptions for non-compliant health claims. Shopify does not automatically enforce this, but non-compliance risks ASA/MHRA enforcement action. Separate approved nutrient function claims from marketing copy in the product description structure:

product.metafields.nutrition.approved_claims = "Vitamin C contributes to normal collagen formation"
// Store approved claims separately from marketing descriptions

Subscription and bundle pricing

Supplement brands typically drive significant revenue from subscriptions (monthly delivery of protein, vitamins etc.). WooCommerce uses plugins like WooCommerce Subscriptions or YITH Subscriptions.

For Shopify, subscriptions require:

Shopify Subscriptions (native, free): Basic recurring billing via Shopify Payments.
ReCharge or Skio: More powerful subscription management with skip/pause/swap features, better for high-volume supplement brands.

During migration, WooCommerce subscription product data does not migrate to Shopify subscriptions — the data models are fundamentally different. Flag subscription products in k-sync with a metafield (nutrition.subscription_eligible = true) and reconfigure subscriptions in Shopify using the chosen app post-migration.

Bundle pricing (buy 2 get 1 free, stack bundles) is handled in Shopify via:

Shopify's native discount codes (BOGO discounts)
Shopify Bundles app for fixed bundle products
Bold Bundles or similar for complex bundle configurations

Allergen and ingredient transparency

UK food labelling law (assimilated from EU Regulation 1169/2011) requires the 14 major allergens to be highlighted. For ecommerce supplement products, this means:

Allergens listed in the product description or a dedicated section
Individual allergen metafields for filtering (gluten-free, dairy-free, soy-free collections)
Full ingredient list in the product description (not just metafields)

Store allergen data as a structured metafield for use in collection filters:

product.metafields.nutrition.allergens = "Milk,Soy"
// Or for allergen-free filtering:
product.metafields.nutrition.dairy_free = "true"
product.metafields.nutrition.soy_free = "true"
product.metafields.nutrition.gluten_free = "true"

Informed Sport and batch testing badges

Informed Sport certification (anti-doping batch testing) is a major trust signal for sports nutrition brands. After migration, render this badge on certified product pages using a metafield-driven section:

product.metafields.nutrition.informed_sport_certified = "true"
product.metafields.nutrition.certification_batch_url = "https://www.informed-sport.com/..."

Batch-test certified products are a competitive differentiator. Ensure these metafields are populated during migration from WooCommerce — they are typically stored as a custom field (_informed_sport or similar) or as a product attribute.

Post-migration checklist for supplement stores

All flavour and size variant combinations present with correct SKUs
Missing size/flavour combos set as unavailable variants (not omitted)
Protein per serving, calories, and caffeine metafields populated
Allergens listed in description AND in structured metafields
Vegetarian, vegan, gluten-free filters working via tags or metafields
Health claims in descriptions reviewed for UK regulatory compliance
Informed Sport certification badge on certified products
Subscription products flagged for ReCharge/Shopify Subscriptions reconfiguration
Best before / shelf life stored for perishable products
Batch testing certificates linked where available

Migrating a supplements and nutrition store from WooCommerce to Shopify (2026)