SIBO

What SIBO actually is

Small intestinal bacterial overgrowth is what the name says: bacteria that belong further down the digestive tract, present in excess in the small intestine. They ferment carbohydrate before you have absorbed it, which produces gas where there should not be much — hence bloating that arrives unusually soon after eating, visible distension, and bowel habits that swing between loose and constipated depending on which gases dominate.

It is usually a consequence rather than a first cause. Slowed motility, previous abdominal surgery or adhesions, structural changes, long-term acid suppression, and conditions such as diabetes or scleroderma all make an overgrowth more likely. That matters enormously for what happens next: if the underlying reason is not addressed, SIBO recurs, and people end up cycling through treatment after treatment wondering what they are doing wrong.

Diagnosis is imperfect, and worth understanding

Breath testing — lactulose or glucose — is the usual route, and it is genuinely imperfect: both false positives and false negatives are common, and interpretation varies between labs. That is not a reason to skip testing. It is a reason to treat the result as one piece of evidence alongside your symptoms and history, rather than a verdict.

It also means that a negative test does not necessarily end the conversation, and a positive one does not mean every symptom you have is explained. Both mistakes are common, and both lead to years of unnecessary restriction.

Where nutrition helps, and where it does not

Plainly: diet does not eradicate SIBO. Eradication is a medical treatment — usually a course of an antibiotic such as rifaximin, sometimes an antimicrobial protocol, and that decision belongs with your physician or gastroenterologist.

What nutrition does, and does well:

• Controls symptoms during treatment, so the weeks of it are liveable
• Feeds you properly through it — malabsorption plus restriction is how people arrive anaemic, deficient in B12 or fat- soluble vitamins, and underweight
• Rebuilds tolerance afterwards, deliberately, rather than leaving you frightened of food
• Addresses what allowed it — meal spacing and motility support, where those are the issue

The restriction trap

Nearly everyone with SIBO has been told to cut something. Low-FODMAP, low-fermentation, elemental, specific carbohydrate, no fibre, no sugar, no fruit. Any of these may help for a few weeks. All of them cause harm if they become permanent.

Prolonged restriction reduces the diversity of the microbiome, which is the opposite of the goal; it makes nutritional adequacy progressively harder; and it has a way of turning into fear of food that outlasts the original illness by years. The most common thing to fix in someone who has had SIBO for a long time is not the overgrowth. It is the eating.

So restriction gets a purpose and an end date, both agreed in advance. If nobody has told you when a diet stops, that is the question to ask.

Recurrence is the real problem

SIBO recurs often — a substantial proportion of people relapse within a year of successful treatment. Repeating the same treatment without asking why tends to produce the same result.

The useful questions are about the cause: is motility the issue, and is anything being done about it? Is long-term acid suppression still necessary, and has anyone reviewed it? Is there an underlying condition driving it? Some of those are nutrition questions and some are medical ones, which is why this works best alongside your physician rather than instead of them.

What the first appointment covers

• Your symptom pattern and its timing — particularly how soon after eating, which points at where the fermentation is happening
• Test results, and an honest reading of what they do and do not show
• What you have already eliminated, for how long, and what it achieved
• Nutritional adequacy: iron, B12, vitamin D, and whether weight has moved
• A plan with a defined end to any restriction, and a reintroduction sequence written down before the restriction starts

When to see a doctor instead

Blood in the stool, unintentional weight loss, iron-deficiency anaemia, difficulty swallowing, persistent vomiting, or a first onset of significant bowel change after 50 are not nutrition problems. They need investigation, promptly, and a dietitian who does not say so is not helping you.

Antibiotic and antimicrobial decisions belong with your physician. Nutrition works alongside that, not in place of it.

Booking, and what it costs

Two routes, and which one is cheaper depends entirely on your plan rather than on which sounds better.

Through insurance. Medical nutrition therapy is a covered benefit on many plans, sometimes with no copay at all. Booking runs through Fay Nutrition, which checks your benefits before the first appointment so you know the number in advance rather than six weeks later.

Self-pay. A flat $140 per session through CognitiveMind — no benefits check, no prior authorization, no denial arriving after the fact. If your coverage is thin, absent, or has a deductible you will not meet this year, this is often the more predictable of the two.

Telehealth, in any of the 18 states where the licence is active.

Common questions