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7 sachets |1 week's supply
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.
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.
FREE UK delivery on orders over £40.
UK express - Monday to Friday delivery.
To compare our supplements for daily use scroll down
One Week Flat can be taken occasionally for 7 consecutive days once a month or on an ongoing basis.
At 61 years of age and a life time of bloating and looking 7 months pregnant most of he time I have tried practically everything on the market and diets and exercise regimes. I came across 7 days flat on yet another desperate web search to find the solution. Well I found it in 7 days flat. First 2 days I felt a bit dizzy ( may be unrelated), by day 4 I saw and felt a difference.. by day 7 the gas reduced to a large extent. Could button and zip trousers with ease. I stopped after 7 days and still felt good. I am travelling later in week and have started again. It is worth giving this product a chance.
This product is a total game changer. I’ve tried all the opti bac products but this one seemed to agree with me the most and I now take these daily. The opti bac team have been great with their customer care and have been committed to helping me find a product that works for me. Thank you!
Used to get so bloated whenever i had my period. I take a course once a month, starting a 2 or 3 days before my period is due
We are the UK's most trusted & recommended brand of friendly bacteria supplements†.
† As determined in an independent survey of 1000 British women.
Proud winners of The Queen's Award for Enterprise 2019 in the international trade category.
Natural food supplement suitable for adults and children (from 4 years onwards) with the following recommendations:
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.
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.
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.
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.
|No. Live Cultures||5 billion|
|Added Ingredients||FOS Fibres|
|Recommended Use||1 sachet daily|
Free UK Delivery over £40
Free standard UK delivery is automatically applied at the checkout when you spend £40.
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 (Tracked): £6.95 (Dispatching Friday 30th December)
Order before 2pm for 1-2 working day delivery to most of the UK*. Orders placed on Friday will be delivered on Monday (next working day). Requires signature.
Please be aware of Christmas Bank holidays.
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.
We offer an excellent worldwide delivery service. For more details, please take a look at our delivery FAQ.
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.
All questions answered by probiotic experts Dr Kate Stephens PhD (Food and Microbial Sciences) BSc(Hons) Medical Biology and Kerry Beeson BSc (Nut. Med.) Nutritional Therapist
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 intolerance (1,2,3). This high-quality supplement contains four, highly-researched friendly bacteria strains combined with natural FOS fibres, which together help to complement the gut microbiome.
(1). Rampengan et al., (2010), ‘Comparison of efficacies between live and killed probiotics in children with lactose malabsorption’. Southeast Asian Journal of Tropical Medicine and Public Health 41: 474-481 (2). D. H. Juers, B. W. Matthews and R. E. Huber, “LacZ β-galactosidase: Structure and function of an enzyme of historical and molecular biological importance,” Protein Science, vol. 21, no. 12, pp. 1792-1807, 2012.# (3). Oak SJ, Jha R. The effects of probiotics in lactose intolerance: A systematic review. Crit Rev Food Sci Nutr. 2019;59(11):1675-1683. doi: 10.1080/10408398.2018.1425977. Epub 2018 Feb 9. PMID: 29425071.
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!
|One Week Flat (7 sachets) - 7 sachets||For Women (14 capsules) - 14 capsules||Every Day (30 capsules) - 30 capsules||Bifido & Fibre (10 sachets) - 10 sachets|
|Suitability||Gas or Bloating||Intimate Flora||General Digestive||Regularity|
|Dosage||1 daily||1-2 daily||1 daily||1-4 daily|