Choose a cereal bar that meets your specific gluten-free or allergen requirement before comparing its nutrition. For weight management, check calories per bar alongside sugars, saturated fat, protein and fibre; a free-from or protein label does not tell you how the bar fits into your overall intake. A gluten-free bar may still contain nuts, milk or soya, so check the exact current pack.
Look for an explicit gluten-free label, then compare the portion and nutrition information. If you have coeliac disease and are considering an oat bar, Coeliac UK notes that standard oats can be contaminated with gluten-containing cereals and that a small number of people are sensitive even to gluten-free oats.
A gluten-free claim does not cover peanuts, tree nuts, milk or soya. Check the ingredients and any precautionary allergen statement for the precise flavour: a gluten-free Nature Valley protein bar can still contain several of these ingredients.
If a bar is part of a planned snack, compare its calories per bar with its protein, fibre, sugars and saturated fat. The NHS explains that managing weight depends on overall energy intake, rather than a single claim on a pack.
Start with the dietary requirement the bar must meet. Then compare the amount you would eat and the nutrition declaration across suitable options.
| Priority | What to check | Your needs |
|---|---|---|
| Gluten and allergens | Look for an explicit gluten-free label where needed. Read the ingredients, emphasised allergens and any “may contain” statement for the exact bar. | I need the free-from claim to cover my particular requirement, not just gluten when I also avoid nuts, milk or soya. |
| Portion and calories | Check kcal per bar and the stated serving size. Use the per 100g figure to compare bars of different sizes. | If I eat a whole bar, I want to know its energy content as eaten rather than rely on how small it looks. |
| Nutrition trade-offs | Compare sugars and saturated fat alongside protein and fibre, using both per-bar and per 100g values where shown. Read traffic-light labelling against the nutrition declaration. | A protein, vegan or gluten-free label alone does not tell me whether the bar fits the snack I have planned. |
| Oat suitability | For an oat bar needed for gluten avoidance, check that the product is explicitly labelled gluten-free. Consider individual tolerance to gluten-free oats. | For coeliac disease, I cannot assume that ordinary oats, “pure oats” or organic oats meet my gluten-free requirement. |
Nature Valley identifies two protein-bar flavours as gluten-free, but the Salted Caramel Nut bar contains peanuts, almond, soya and milk.
Check the current ingredients and any precautionary allergen statement for the exact flavour you intend to eat.
Bars with similar front-of-pack claims can have different nutrition declarations. Action on Salt & Sugar’s November 2025 review of 458 snack bars from 10 major retailers recorded 55% as high in saturated fat and 37% as high in sugars; those figures describe the bars reviewed, not every cereal bar.
Compare kcal, sugars and saturated fat per bar and per 100g before considering protein and fibre among options that meet your dietary requirements.
Coeliac UK says standard oats can be contaminated with wheat, barley or rye during production. Descriptions such as “pure” or “organic” do not establish gluten-free status.
Where gluten avoidance is required, choose an oat bar explicitly labelled gluten-free and take account of any individual sensitivity to gluten-free oats.
Recipes and ranges can change; Alpen, for example, lists several former bar flavours as no longer made.
Use a product page to narrow your choices, then check the current pack’s ingredients, allergen statement and nutrition declaration.
Brand ranges differ, and a claim attached to one flavour does not necessarily apply to another. Check the precise bar before making a dietary or nutrition comparison.
A reference point for gluten-free protein bars. Nature Valley UK identifies Protein Peanut & Chocolate and Protein Salted Caramel Nut as the gluten-free products in its range.
Offers plant-based protein bars and flapjacks for shoppers considering a vegan format.
Offers a selection of gluten-free cereal bars, according to its UK range information.
Its Oat Boost flapjacks provide an oat-based format to compare by portion and nutrition declaration.
A useful reminder that portion information and free-from suitability are separate checks.
A comparison brand to check carefully when gluten avoidance is essential.
These options include TREK oat flapjacks and two Nature Valley protein-bar flavours. For any bar you need to be gluten-free, confirm the wording and other allergens on its current pack, then compare its nutrition per bar.
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An oat-flapjack option for a planned snack; TREK describes its bars as plant-based. If you need to avoid gluten, confirm this flavour’s gluten-free wording and allergens on the pack, and compare its kcal and sugars per bar.
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A cocoa oat-flapjack format from TREK’s plant-based range. Check this flavour’s current gluten-free label and allergen statement if either affects your choice; use its per-bar calories, sugars and saturated fat for the snack comparison.
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Nature Valley UK identifies this flavour as gluten-free and describes each 40g bar as providing around 10g protein and 4g fibre. It contains peanuts, almond, soya and milk. Check the current pack’s calories and full nutrition declaration alongside those ingredients.
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Nature Valley UK identifies this flavour as gluten-free and lists approximately 10g protein and 196 kcal per 40g bar. It contains peanuts, soya and milk; read the current pack for its full allergen statement and compare sugars and saturated fat with other suitable bars.
No. A gluten-free claim does not mean the bar is free from peanuts, tree nuts, milk or soya. Nature Valley’s gluten-free Protein Salted Caramel Nut bar, for example, contains peanuts, almond, soya and milk; check the precise product’s ingredients and any precautionary allergen statement.
Choose an oat bar explicitly labelled gluten-free rather than assuming ordinary oats are suitable. Coeliac UK explains that standard oats can be contaminated with wheat, barley or rye, and that a small number of people remain sensitive to gluten-free oats. Take account of your individual advice about oats.
Use both: kcal per bar shows the amount in one bar, while per 100g values help compare different bar sizes. The NHS notes that nutrition information is given per 100g and sometimes per portion; check whether the stated portion matches what you intend to eat.
No. Protein is one part of the nutrition declaration, not a measure of how a bar fits your overall energy intake. Compare kcal, sugars and saturated fat per bar, and meet any gluten-free or other allergen requirement before deciding between flavours.