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One Week Flat

28 sachets |4 weeks' supply

  • Optibac Probiotics One Week Flat | highly researched strains of probiotics suitable for bloating | 28 sachets
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  • Optibac Probiotics One Week Flat - For Bloating
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  • Optibac Probiotics One Week Flat Acidophilus Probiotic
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  • One Week Flat - Most Recommended - For Bloating
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    Optibac Probiotics One Week Flat | highly researched strains of probiotics suitable for bloating | 28 sachets
    Optibac Probiotics One Week Flat Bestselling Brand
    Optibac Probiotics One Week Flat - For Bloating
    Optibac Probiotics One Week Flat Gold Standard Science
    Optibac Probiotics One Week Flat 5 Star Reviews
    Optibac Probiotics One Week Flat Acidophilus Probiotic
    Optibac Probiotics One Week Flat - Natural Ingredients
    Optibac Probiotics One Week Flat Easy to take
    One Week Flat - Most Recommended - For Bloating
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    Optibac Probiotics One Week Flat (28 sachets) pack back
    Optibac Probiotics One Week Flat (28 sachets) pack side shot
    One Week Flat 28's - front
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    Camilla Gray DipCNM Nutritional Therapist
    My personal discovery of live cultures started with One Week Flat 10 years ago and it’s one I still use and recommend regularly, especially before holidays or festive periods.
    Camilla Gray
    Camilla Gray DipCNM Nutritional Therapist

    Who is it for?

    Optibac One Week Flat is an affordable, 7-day course of friendly bacteria in easy-to-take sachets. It is gluten-free and therefore may be suitable for those with bloating.

    Pack size

    £9.99
    7 sachets
    £29.99
    28 sachets
    Purchase type

    FREE UK delivery on orders over £10.

    UK express - Monday to Friday delivery 

    See our Delivery & Returns for more information.

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    • Gluten free

      Gluten free

    • Vegan

      Vegan

    • Yeast free

      Yeast free

    • No added sugar

      No added sugar

    • Artificial colour free

      Artificial colour free

    Key benefits

    Friendly bacteria suitable for those with bloating

    A short term friendly bacteria supplement which complements the natural gut bacteria.

    • High-quality supplement Contains strains proven to survive stomach acidity and reach the gut alive 
    • Combination formula with FOS fibres A multi-strain supplement containing four live cultures strains combined with FOS fibres
    • Using only targeted strains Including Lactobacillus acidophilus/helveticus Rosell-52
    • Easy to take and flavourless Individual powder sachets can be mixed into cool, non-acidic food or drink
    • Suitable for those with occasional bloating Gluten free supplement with strains shown to produce digestive enzymes like lactase and α-glucosidase, involved in the breakdown of lactose in milk & starch
    • Can be taken short-term or ongoing Ideal for occasional use, simply take for 7 consecutive days, or can be taken daily
    • A more natural option Vegan and free from added sugars and flavourings often found in other live cultures supplements
    • From the UK's most recommended brand Optibac is the brand of friendly bacteria supplements most recommended by UK consumers†

     

    Optibac Probiotics strains

    • Lactococcus lactis Rosell-1058
    • Lactobacillus casei Rosell-215
    • Lactobacillus acidophilus/helveticus Rosell-52
    • Bifidobacterium bifidum Rosell-71

    Added nutrients

    • FOS fibres
    See full ingredients list
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    General digestive

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    Complements gut bacteria

    Customer Reviews

    Customer reviews have been collected on our website or independently through Trustpilot where no moderation is possible. Reviews are not endorsed by us and should not be regarded as medical or health advice. The top 3 reviews have been hand selected as our recent favourites, please click 'View all product reviews' below to explore more reasons why customers love this product.

    Help & advice

    Our team of qualified experts are available for free personalised supplement advice. If you're not sure where to start or your needs have recently changed, please get in touch.

    Contact us
    Louise Mason
    Louise Mason BA(Hons) DipCNM Nutritional Therapist, DipCNM Naturopath, mANP
    optibac

    Why choose us?

    We are the UK's most trusted & recommended brand of friendly bacteria supplements as determined in an independent survey of 1000 people† 

    We use the most researched strains of friendly bacteria in the world with each supplement designed to target individual needs and life stages.

    • How to use

    • Ingredients

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    • Delivery & returns

    • How to use

      Recommended use

      Natural food supplement suitable for adults and children (from 4 years onwards)

       

      One Week Flat has the following recommendations:

      • Take 1 sachet daily for 7 consecutive days, preferably with breakfast.
      • Pour an inch of water into a tall glass, leaving plenty of room for swirling.
      • Shake the sachet before gently sprinkling the powder into the glass.
      • Vigorously swirl the water around in the glass making sure the powder is dissolved.

      We highly recommend you take One Week Flat for 7 consecutive days. Many consumers like to take this course once a month. However, it can be taken on an ongoing basis or as desired.

      Storage

      • Store in a cool, dry place below 25°C and out of direct sunlight.

      Safety

      Live cultures are not recommended for those with serious medical conditions e.g. those who are severely immunosuppressed, have pancreatitis, are in the ICU, have melaena, have a central venous catheter, infants with short bowel syndrome, or patients with open wounds following major surgery; unless under a doctor's care. Keep out of reach of children.

      Gut health supplements are not intended to prevent, treat or diagnose any medical conditions. If taking probiotic supplements for gut health, note that these should not be used as a substitute for a varied and balanced diet and a healthy lifestyle. If you are taking any medications or have a serious medical condition, consult a doctor before use. Optibac supplements will not cause dependency and may be used on an ongoing basis.

    • Ingredients

      Live Cultures

      • Lactococcus lactis Rosell-1058
      • Lactobacillus casei Rosell-215
      • Lactobacillus acidophilus/helveticus Rosell-52
      • Bifidobacterium bifidum Rosell-71

      Ingredients

      Maltodextrin (natural source); Fructooligosaccharides (FOS 0.3g); Live cultures: Bifidobacterium bifidum Rosell-71, Lactobacillus casei Rosell-215, Lactococcus lactis Rosell-1058 and Lactobacillus acidophilus/helveticus Rosell-52

      Each sachet guarantees 5 billion live cultures + 0.3g FOS fibres.

      Suitability

      • Vegan
      • Vegetarian
      • Gluten free
      • Yeast free
      • No added sugar
      • Suitable during pregnancy
      • Suitable during breastfeeding
      • GMO free
      • Flavourless
      • Free from artificial flavourings, colourings and preservatives
      • No chemicals or parabens

      Following the taxonomic updates by a global team of scientists and published in April 2020, a reclassification has been advised for the L. casei species. The casei strain in the Optibac One Week Flat product is now also known as Lacticaseibacillus casei Rosell-215.

      Visit the Probiotics Learning Lab to find out more about friendly bacteria supplements and bloating.

      Format Sachet
      No. Live Cultures 5 billion
      Added Ingredients FOS Fibres
      Recommended Use 1 sachet daily
      Age Range Adult

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    • Delivery & returns

      UK Delivery

      Please note, the office will be closed after Friday 20th December and reopen on Thursday 2nd January 2025.

      We will be dispatching 23rd, 27th & 30th December. Please expect delays over the festive period.

      Free UK Delivery over £10 
      Free standard UK delivery is automatically applied at the checkout when you spend £10.

      Standard 2nd class: £2.50 
      Allow 4-10 working days (Monday - Friday) for delivery 

      1st class: £3.95
      Allow 1-3 working days (Monday - Friday) for delivery 

      Express Next Day, order before 2pm (Tracked): £6.95
      Allow 1-2 working day delivery to most of the UK*. Orders placed on Friday will be delivered on Monday (next working day). Requires signature.

      Shipments will be dispatched via DHL or FedEx, the service will be selected depending on the delivery location.

      *Express delivery may exclude the Channel Islands, Herm Island, Isle of Man, Isle of Wight, Northern Irish postcodes BT18 & upwards, Sark, Scottish borders and offshore and a small number of remote mainland destinations as determined by our delivery courier. 

      Good to know

      • We'll send you an email to confirm once your parcel has been dispatched.
      • For delivery queries, please call us on +44 (0)1264 339 770 or email enquiries@optibacprobiotics.com. 
      • Orders placed before 2pm are typically dispatched on the same working day.
      • Delivery within the UK and Northern Ireland has a fixed price, regardless of the size and weight of your order. 
      • Delivery times are estimates and not guaranteed unless otherwise stated.

      International Delivery

      We offer an excellent worldwide delivery service. For more details, please take a look at our delivery FAQ.

      Returns

      If you have changed your mind, you can return goods, at your cost, unopened within 14 days for refund or exchange, this does not affect your statutory rights.

    Customer Questions

    All questions answered by probiotic experts Dr Kate Steed PhD (Food and Microbial Sciences) BSc(Hons) Medical Biology and Louise Mason BA(Hons) DipCNM Nutritional Therapist, DipCNM Naturopath, mANP

    Initially it’s best to take Optibac One Week Flat daily for one week to complement your natural gut bacteria. After that, people take a week’s course every month, or whenever they feel they need it. Others prefer to take one sachet every day on an ongoing basis. All of these options are absolutely fine! See what suits you best.

    With only 7.72 calories per sachet, and 0g of fat, it’s easy to include Optibac One Week Flat in your calorie-controlled diet. The carbohydrate content is mostly from natural FOS fibres which are indigestible with barely any calorific content.

    Yes! One Week Flat is carefully formulated to have a slightly sweet, ‘neutral’ flavour which most people find pleasant to take. However, be reassured that the supplement contains no added flavourings, sugar, or sweeteners – the mild sweet taste comes from the natural Fructooligosaccharide (FOS) fibres.

    One Week Flat is dairy and gluten-free, so is a perfect supplement for those with food-related bloating or lactose intolerance1,2,3. This high-quality supplement contains four, highly-researched friendly bacteria strains combined with natural FOS fibres, which together help to complement the gut microbiome.

    Read references

    Definitely! Friendly gut bacteria are not gender-specific. Optibac One Week Flat live cultures can be taken by everyone over the age of 4 years: women, men, trans and non-binary people too!

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