For an office packed lunch, start with the calories in the whole bar you plan to eat, then check sugars, saturated fat and any ingredients you need to avoid. A smaller bar may suit a lighter snack, while a protein-focused bar may suit a different priority; claims such as ‘no added sugar’ or ‘high protein’ do not tell you the calorie count.
If a bar is going into your lunchbox or desk drawer, the calories in one complete bar matter more to your choice than a front-of-pack claim. Portion size, sugars and saturated fat are worth checking alongside them.
If protein or fibre is your priority, compare the amounts per bar with its calorie count. The products discussed here have different serving sizes, so a higher nutrient figure does not answer every packed-lunch question on its own.
Read the current pack’s ingredients, allergen declaration and ‘may contain’ statements. A vegan or gluten-free claim addresses that stated criterion; it does not establish that a bar is free from nuts or other allergens.
Choose the portion you would put in your lunch first. Then use the per 100g figures to compare bars of different sizes on the same basis.
| Priority | What to check | Your needs |
|---|---|---|
| Calories and portion | Check kcal for the whole bar or boost you will eat. Compare kcal per 100g as well when bar weights differ; NHS food-label guidance explains the per 100g basis. | I want to know what one bar adds to my packed lunch, without mistaking a smaller bar for a lower-calorie bar of the same size. |
| Sugars and saturated fat | Read both values per bar and per 100g. Treat ‘no added sugar’, protein and fibre claims separately from the full nutrition panel. | A front-of-pack claim catches my eye, but I also want to see the total sugars and saturated fat in the portion I would eat. |
| Protein and fibre | Compare grams per bar alongside kcal and serving weight. For example, Tesco lists 12g protein, 12g fibre and 159 kcal for a 44g TREK High Protein Choc Caramel bar. | If protein or fibre matters more to me than choosing the lowest-calorie example, I can make that trade-off using the figures for the exact bar. |
| Ingredients and allergens | Check the current ingredients list, highlighted allergens and ‘may contain’ wording. Verify dietary claims against the criterion that matters to you. | I need a bar that fits my dietary exclusions, not one that merely carries a different dietary claim. |
| Keeping it at work | Follow the storage instructions and best-before date on the exact pack, and check whether its pack format works for your lunch routine. | For a bar kept in a lunchbox or desk drawer, I want to know how that particular product should be stored. |
A fibre, protein or no-added-sugar claim does not establish that a bar is low in calories, total sugars or saturated fat. In its 2025 UK supermarket snack-bar analysis, Action on Salt and Sugar reported that 37% of the bars reviewed would be high in sugars and 55% high in saturated fat under voluntary traffic-light thresholds. Those are shares of products reviewed, not shares of shoppers.
Check the exact bar’s kcal, sugars and saturated fat per serving, then use its per 100g figures for comparisons across sizes.
The examples in this article range from 30g boosts to 44g bars. A smaller bar can show fewer calories per bar without having fewer calories per 100g.
Compare the whole portion you intend to eat first, then check per 100g when deciding between different bar sizes.
Fruit-and-nut and protein bars can have different ingredients and precautionary allergen statements. A vegan or gluten-free claim does not mean nut-free.
Read the current pack’s full ingredients and allergen wording against your dietary requirements before buying.
Alpen’s product information identifies several former bar variants that are no longer made. An old listing may not describe the pack you can buy now.
Confirm the current variant, pack size and nutrition information before using an older product name in your regular lunch shop.
These figures describe specific bars, not every product from each brand. Compare the current pack for any variant you choose.
Graze Cocoa Vanilla Oat Boosts provide a smaller oat-based example for comparing office snack portions.
Blueberry Muffin is a fruit-and-nut bar for shoppers comparing its stated dietary claims with the complete nutrition panel.
High Protein Choc Caramel is a point of comparison when protein and fibre matter alongside calories.
Protein Chocolate & Coffee illustrates why the protein figure should be read with the calorie count.
Peanuts & Dark Chocolate Protein Bar is a nut-and-chocolate option with stated protein and fibre figures.
Alpen cereal bars may appear in older snack-bar lists, so the precise current variant matters.
These options include smaller oat, fruit-and-nut and cereal bars, plus protein bars. Use the exact variant and portion size when comparing them for an office packed lunch.
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The 30g boost size gives you a defined portion to compare with other lunchbox bars. Check the Cherry Bakewell pack’s calories, sugars and allergen wording rather than applying figures from another Graze flavour.
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For a fruit-and-nut option, nākd. lists 131 kcal, 17g total sugars and 3.3g fibre per 35g Blueberry Muffin bar. Its no-added-sugar claim does not mean sugar-free; check the nut ingredients and current pack.
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This protein-bar format may be relevant if protein is a selection priority rather than the smallest portion. Compare the 50g bar’s calories, sugars and saturated fat with those of the other options, and check its allergen declaration.
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The 21.5g bar is a smaller portion than the protein bars shown here. If calories per whole bar are your starting point, also compare per 100g values so the difference in bar size remains clear; check sugars and allergens on the pack.
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Choose between this 50g protein-bar variant and a smaller snack by looking at the complete bar’s nutrition panel, not its product category alone. Check calories and saturated fat alongside protein, and read the current allergen declaration.
No. The claim does not state the bar’s calorie count or total sugars. For example, nākd. lists 131 kcal and 17g total sugars per 35g Blueberry Muffin bar, which it labels no added sugar. Check the whole bar’s nutrition panel.
Use both: per-bar kcal describes the portion you plan to pack, while per 100g figures help you compare differently sized bars. NHS food-label guidance explains that nutrition information is given per 100g and may also be shown per portion.
No. The specific products differ: Tesco lists 159 kcal for a 44g TREK High Protein Choc Caramel bar, Nature Valley lists 197 kcal for its 40g Protein Chocolate & Coffee bar, and Eat Natural lists 220 kcal for its 40g Peanuts & Dark Chocolate Protein Bar. Compare protein and fibre with calories for the exact variant.
Read the current pack’s ingredients, highlighted allergens and ‘may contain’ statements. Do not assume a vegan, gluten-free or dairy-free claim also means nut-free or suitable for another dietary exclusion.
Follow the storage instructions on that bar’s pack and check its best-before date. Nature Valley directs buyers of its Protein Chocolate & Coffee bar to store it in a cool, dry place, but instructions can differ between products.