Bilva for IBS: Does It Work?
Does Bilva (Aegle marmelos, बिल्व), also called Bael, help with irritable bowel syndrome? Yes, with one caveat that decides whether the herb works for you or against you: only the unripe (green) fruit treats IBS-D. The ripe fruit is mildly laxative and is used for chronic constipation. Mistaking ripe for unripe is the single most common error in self-prescription.
Used correctly, unripe Bilva is the premier classical drug for diarrhea-predominant IBS and Grahani Roga, the Ayurvedic disease that maps almost exactly to modern IBS. The Bhavaprakash Nighantu classifies unripe Bilva as Grahi (binding/absorbent), Deepani (kindles digestive fire), and Pachani (digestive), the three actions that together address the failed "holding" function at the heart of Grahani. Charaka Chikitsa Sthana 15 names Bilva among the first-line Sangrahi drugs for chronic loose stool, and the Ashtanga Hridaya specifically warns that ripe Bilva aggravates all three doshas while unripe Bilva is the treatment of choice for diarrheal disease.
Among the herbs Ayurveda offers for IBS, Bilva fills a unique niche: chronic, post-infectious, Vata-Pitta IBS-D where Agni is weak, the bowel is unstable, and stool is loose, frothy, or unformed. Its Ushna Virya (warming potency), Kashaya-Tikta rasa (astringent-bitter taste), and tannin-mucilage chemistry combine binding with mucosal protection in a way that cooler astringents cannot. For the IBS-D patient who also has gas, cramping, and a cold abdomen, Bilva is the lead herb in classical practice.
How Bilva Helps with IBS
Unripe Bilva acts on IBS through four overlapping mechanisms, three classical, one modern. The unifying theme is restoration of Grahani function: the small intestine regains its ability to "hold" food long enough for proper digestion, while the loose, hypermotile bowel is bound and the inflamed mucosa is coated.
1. Sangrahi action: tannin-mediated binding of loose stool
Unripe Bael fruit is dense in hydrolyzable tannins and astringent polyphenols. Sangraha in Ayurvedic pharmacology means "holding together", the action of re-forming a watery stool into a soft, shaped one. Mechanistically, tannins precipitate luminal proteins, tighten enterocyte junctions, and reduce passive water loss across an inflamed mucosa. This is the action Charaka calls Sangrahi and it directly counters the IBS-D pattern of urgent, loose, frequent stool.
2. Mucilage and pectin: a soothing demulcent layer
Unripe Bilva pulp contains substantial pectin and a marmelos-specific mucilage. Taken as powder in warm water, decoction, or paste, this gel-like film coats the irritated small-bowel and colonic mucosa, physically separating raw villi from luminal irritants long enough for the epithelium to heal. This is why Bilva works particularly well in post-infectious IBS, where the underlying lesion is mucosal inflammation left behind by an acute infection.
3. Ushna Virya: rekindling Agni in cold, weak-fire IBS
Most anti-diarrheal astringents are cooling. Bilva is the exception: Kashaya-Tikta Rasa (astringent-bitter taste) with Ushna Virya (warming potency) and Katu Vipaka (pungent post-digestive effect), with light and dry qualities. In IBS, classical pathology centres on Vishama Agni, irregular digestive fire driven by deranged Vata. Cooling astringents further dampen an already unstable fire. Bilva does the opposite: it binds while warming, addressing both ends of the cycle. The Bhavaprakash specifically calls unripe Bilva Deepana, kindling, for this reason. It pacifies Vata and Kapha while only mildly increasing Pitta at high doses, making it suitable for the Vata-Pitta combined pattern that characterises most IBS-D.
4. Modern: marmelosin and tannins reduce intestinal hypermotility
Modern phytochemistry has confirmed the classical claim. Aegle marmelos extracts have been validated against castor-oil and magnesium-sulphate-induced diarrhea in animal models, the two standard pharmacological assays. Active constituents marmelosin (the principal coumarin), tannins, and flavonoids reduce intestinal fluid secretion, prolong transit time, and show antimicrobial activity against E. coli, Shigella, and Vibrio strains. The anti-inflammatory action on intestinal mucosa, documented in pre-clinical models, addresses the visceral hypersensitivity and mast-cell activation that drive IBS-D pain. Large human trials are still limited, with most clinical evidence drawn from open-label Ayurvedic case series in IBS-D and chronic Grahani.
How to Use Bilva for IBS
The unripe vs ripe rule, non-negotiable for IBS
This deserves repetition because it is the single error that derails Bilva therapy for IBS. Unripe (green) Bilva fruit is astringent, mucosal-protective, and binds loose stool, use this for IBS-D. Ripe (yellow-orange) Bilva is mildly laxative, has a collapsed tannin profile, and is used for chronic constipation, taking it for IBS-D will make symptoms worse. When buying powder, look for explicit "unripe fruit" or "kaccha bilva" labelling. Authentic Ayurvedic brands list the part used; bulk-market "bael powder" without specification is usually ripe and unsuitable.
Forms used for IBS
- Unripe Bilva fruit powder (Bilva Churna), the workhorse form for daily IBS-D protocols.
- Bilvadi Churna, compound powder pairing Bilva with Shunthi, Musta, and other Sangrahi drugs; the most-used IBS-D formula.
- Bilvashtaka Churna, eight-herb classical formula with Bilva as the lead, indicated specifically for chronic IBS-D with urgency.
- Fresh unripe pulp juice, 15 to 30 ml; seasonal (April to June in India) and most potent for acute mucosal flare.
- Bilva Panaka, traditional drink of unripe pulp infused in water with a touch of jaggery and rock salt, used during convalescence and Agni-rebuild.
Standard dosing for IBS
| Goal | Form | Dose | Anupana (Vehicle) | Timing |
|---|---|---|---|---|
| Chronic IBS-D, post-infectious loose stool | Unripe Bilva fruit powder | 3 to 6 g twice daily | Buttermilk (takra) or warm water | 30 min before meals |
| Vata-Pitta IBS-D with cramping and gas | Bilvadi Churna | 3 to 6 g twice daily | Buttermilk (takra) | Before lunch and dinner |
| IBS-D with urgency and burning | Bilvashtaka Churna | 3 to 6 g twice daily | Buttermilk or warm water | Before meals |
| Acute IBS-D flare with frothy stool | Fresh unripe pulp juice | 15 to 30 ml twice or thrice daily | Equal water + pinch of rock salt | Until settled |
| Convalescence and Agni rebuild | Bilva Panaka | 100 to 200 ml | Self (sipped) | Mid-morning, mid-afternoon |
The classical Bilva-Takra protocol
The single most-cited classical regimen for chronic Grahani and IBS-D is Bilva taken with takra (cultured buttermilk). Takra is itself a Grahi-Deepana, it binds while kindling fire, and the combination is described in Charaka Chikitsa 19. Practical recipe: 3 to 6 g unripe Bilva churna stirred into 100 to 150 ml of fresh, lightly salted, slightly diluted buttermilk, taken twice daily before meals for 4 to 8 weeks. Buttermilk should be made from cow milk, whisked with twice the volume of water, lightly salted, and consumed within an hour. This single protocol resolves a substantial fraction of chronic IBS-D presentations on its own.
Anupana selection for IBS
Anupana (the vehicle) matters as much as the herb itself in IBS. For most IBS-D patterns, thin fresh buttermilk is the ideal carrier, it is itself Sangrahi and synergises with Bilva. Warm water is the simpler default. Rice gruel works well during post-infectious recovery as a gut-resting carrier. Avoid milk and yogurt during active flares; they are heavier and less tolerated than thin takra.
Duration
For chronic IBS-D, expect 4 to 8 weeks of consistent twice-daily use to see durable reduction in stool frequency, normalised consistency, and improved appetite. The underlying lesion is mucosal and takes time to heal. Reassess at week 2: if there is no improvement, reconsider the dosha pattern, predominantly Pitta-IBS with mucus, blood, or fever points to Kutaja rather than Bilva. After 8 weeks of relief, taper to a maintenance dose or shift to a background tonic.
What to avoid
- Ripe Bilva, will worsen IBS-D. Use only unripe fruit, Bilvadi Churna, or Bilvashtaka Churna.
- Active high-Pitta IBS with severe burning, mucus, or blood, lead with cooling herbs first; reintroduce Bilva once the acute Pitta settles.
- IBS-C with hard, dry stool, astringent Bilva will make it worse. Haritaki or Triphala is the appropriate herb in that case.
- Severe dehydration during a flare, herbal binding does not replace fluids and electrolytes. Pair with ORS and seek medical care for persistent vomiting or signs of dehydration.
- Stacking with anti-motility drugs (loperamide), pick one. Combining can over-bind and cause constipation.
Frequently Asked Questions
Ripe vs unripe Bilva for IBS, why does it matter so much?
This is the single most important distinction in using Bilva for IBS, and the place where most self-prescription goes wrong. Unripe (green, raw) Bilva is anti-diarrheal, high in tannins, mucilaginous gum, and Sangrahi action; this is the form for IBS-D. Ripe Bilva is laxative, the starches and gums convert to sugars during ripening, the tannin profile collapses, and the fruit becomes a mild bulk laxative used classically for chronic constipation. They are pharmacologically opposite preparations of the same fruit. Sweet bael sherbet, ripe-pulp jams, and unspecified "bael powder" sold in bulk markets are usually ripe-fruit products and will worsen IBS-D. Always verify "unripe" or "raw fruit" on the label, or buy a classical formulation like Bilvadi Churna or Bilvashtaka Churna where the part used is standardised.
How long does Bilva take to work for IBS?
For acute IBS-D flares, expect noticeable firming of stool within 2 to 4 days of consistent twice-daily dosing. For chronic IBS-D and post-infectious patterns, plan on 4 to 8 weeks of daily use to see durable resolution, the underlying mucosal lesion takes time to heal. Improvements in cramping, gas, and appetite often appear earlier, within the first 1 to 2 weeks, and signal that the Agni-restoring action is working. If there is no improvement at week 2, reconsider the dosha pattern: severe Pitta-IBS with mucus or burning needs Kutaja, not Bilva.
Bilva vs Cumin for IBS, which is better?
Different roles. Bilva is the lead binder for IBS-D: it stops loose stool, coats inflamed mucosa, and rebuilds Agni in chronic, post-infectious, Vata-Pitta patterns. Cumin is the lead carminative: it relaxes intestinal smooth muscle, reduces gas, and addresses the cramping and bloating that accompany all IBS subtypes. They are complementary rather than competing. Most chronic IBS-D protocols use both, Bilva or Bilvadi Churna for the binding action, cumin (often as part of CCF tea with coriander and fennel) after meals for the gas and cramping. If you must choose one, match the dominant symptom: loose stool reaches for Bilva; gas and spasm reaches for cumin.
Bilva vs Shatavari for IBS?
Different niches. Bilva is the binder for IBS-D with weak Agni and unstable bowel, its action is astringent and warming. Shatavari is the cooling, demulcent, restorative herb for Pitta-IBS with burning, inflammation, and depletion, particularly in patients who are thin, stressed, or under-weight; classical home-remedy texts pair Shatavari with kama dudha and arrowroot for IBS where Vata is pushing Pitta into the colon. Use Bilva for the cold, chronic, loose-stool pattern; use Shatavari for the hot, depleted, burning pattern. They can be combined when both elements are present, Shatavari in the morning for cooling and rebuilding, Bilva or Bilvadi Churna before lunch and dinner for binding.
Can I take Bilva with my IBS medication?
For most patients, yes, with caution about one specific class. Bilva pairs safely with antispasmodics and most other IBS pharmaceuticals. The exception is anti-motility drugs like loperamide: combining Bilva with loperamide can over-bind and cause rebound constipation. Pick one or the other, and if you switch from loperamide to Bilva, give a 24-hour gap. Bilva also pairs well with probiotics and oral rehydration solutions, the classical Bilva-Takra protocol is itself a probiotic combination. Always tell your prescribing doctor what you are taking, especially during the first 4 weeks when the response is being assessed.
Recommended: Start Bilva for IBS
If you want to start using Bilva for IBS today, the simplest classical starting point is unripe Bilva fruit powder taken with thin buttermilk twice daily, the time-tested Bilva-Takra protocol for chronic IBS-D and Grahani.
Best form: Unripe Bilva fruit powder (Bilva Churna) at 3 to 6 g twice daily, 30 minutes before meals. The unripe form binds loose stool, coats inflamed mucosa, and rekindles Agni. Do not use ripe Bilva for IBS-D, it is laxative and will make symptoms worse. If a single-herb churna is hard to find, Bilvadi Churna (Bilva paired with Shunthi and other Sangrahi drugs) is the most common ready-made compound for this use.
Kitchen recipe (Bilva-Takra): Whisk fresh cow-milk yogurt with twice the volume of water, lightly salt it. Stir 3 to 6 g (about one teaspoon) of unripe Bilva powder into 100 to 150 ml of this thin buttermilk. Drink 30 minutes before lunch and dinner. Use within an hour of preparation. Continue daily for 4 to 8 weeks.
Dosha fork:
- Vata-Pitta IBS-D with cramping and gas: use Bilvadi Churna with takra; add a pinch of Hingu (asafoetida) roasted in ghee to your cooked food.
- IBS-D with strong urgency and burning (Pitta-leaning): reduce dose to 2 to 3 g, add Shatavari in the morning for cooling support.
- Post-infectious IBS-D with weak appetite: Bilva Panaka (unripe pulp infused in water with a pinch of jaggery and rock salt), sipped between meals.
Find Unripe Bael Fruit Powder on Amazon ↗ Find Bilvadi Churna ↗
Safety note: Verify "unripe fruit" or "kaccha bilva" on the label, ripe Bael is laxative and will worsen IBS-D. Do not combine with loperamide; pick one. Avoid Bilva if your IBS pattern is constipation-predominant with hard, dry stool, the astringent action will make it worse. Blood in stool, fever, nocturnal symptoms, or unintentional weight loss require medical evaluation before assuming IBS.
Safety & Precautions
Contraindications: Dried immature fruit if constipated; fresh fruit for congestion,; ama, weak digestion
Safety: No drug–herb interactions are known.
Other Herbs for Irritable Bowel Syndrome
See all herbs for irritable bowel syndrome on the Irritable Bowel Syndrome page.
▶ Classical Text References (5 sources)
- Atisara (diarrhea)
- Pravahika (dysentery)
- Grahani (malabsorption/IBS)
- Shotha (edema/swelling)
- Hridroga (heart disease)
- Vataroga (Vata disorders)
- Kapharoga (Kapha disorders)
Source: Bhavaprakash Nighantu, Varga 3
प वं सद ु ज ु रं व वं दोषलं पू तमा तम ् द पनं कफवात नं बालं, ा युमयं च तत ् Bilva phala (bael fruit) when ripe is hard to digest, aggravates the doshas and causes flatus;
— Astanga Hridaya Sutrasthan, Annaswaroopa Food
Tikta Gana – group of bitters :त तः पदोल ाय ती वालकोशीर च दनम ् भू न ब न ब कटुका तगरा गु व सकम ् न तमाला वरजनी मु त मूवाट पकम पाठापामागकां यायोगुडू चध वयासकम ् प चमल ू ं महा या यौ वशाल अ त वषावचा Patoli, Trayanti – Gentiana kurroa, Valaka, Usira – Vetiveria zizanioides, Chandana – Sandalwood, Bhunimba – The creat (whole plant) – Andrographis paniculata, Nimba – Neem – Azadirachta indica, Katuka – Picrorhiza kurroa, Tagara – Indian Valerian (root) – Valeriana wallichi, Aguru, Vatsaka – Hol
— Astanga Hridaya Sutrasthan, Rasabhediyam Tastes, Their
Either Rasanjana (Aqueous extract of Berberis aristata), Brihat Pancamula (Agnimantha, Shyonaka, Gambhari, Patala, Bilva), Guggulu – along with the fresh juice of Agnimnatha is suitable;
— Astanga Hridaya Sutrasthan, Dvividha Upakramaneeya
Similar is the case of Anuvasana – fat enema and Matra basti – fat enema with very little oil 34-36 Anu taila जीव तीजलदे वदा जलद व से यगोपी हमं दाव व मधुक लवागु वर पु ा व ब वो पलम ् धाव यौ सरु भं ि थरे कृ महरं प ं ु ट रे णक ु ां कि ज कं कमला वलां शतगुणे द ये अ भ स वाथयेत ् ३७ तैला सं दशगण ु ं प रशो य तेन तैलं पचेत ् स ललेन दशैव वारान ् पाके पे चदशमे सममाजद ु धं न यं महागुणमुश यणुतैलमेतत ् ३८ Jivanti, Jala, Devadaru, Jalada, Twak, Sevya, Gopi (sariva), Hima, Darvi twak, Madhuka, Plava, A
— Astanga Hridaya Sutrasthan, Nasya Vidhi Nasal
प वं सद ु ज ु रं व वं दोषलं पू तमा तम ् द पनं कफवात नं बालं, ा युमयं च तत ् Bilva phala (bael fruit) when ripe is hard to digest, aggravates the doshas and causes flatus;
— Astanga Hridaya Sutrasthan, Annaswaroopa Food
Source: Astanga Hridaya Sutrasthan, Annaswaroopa Food; Rasabhediyam Tastes, Their; Dvividha Upakramaneeya; Nasya Vidhi Nasal
In addition to the above, the following items too should be kept available there – two grinding stones, two small pestles, two mortars, one untamed bull, two gold and silver cases for keeping needles, various surgical instruments that are sharp and prepared of metals, two bedsteads made of bilva (Aeglemarmelos Corr.
— Charaka Samhita, Sharira Sthana — Human Body & Embryology, Chapter 8: Guidelines for Lineage (Jatisutriya Sharira / जातिसूत्रीय शरीर)
Out of this, cakes of one bilva or pala each should be prepared.
— Charaka Samhita, Chikitsa Sthana — Therapeutic Principles, Chapter 11: Chest Injury and Emaciation Treatment (Kshatakshina Chikitsa / क्षतक्षीणचिकित्सा)
Take 40 gm fine powder each of svarajjikā and yava-kshara, four varieties of salt, iron bhasma, trikatu, triphala, pippalimula, pealed seeds of vidanga, mustaka, ajamodā, devadāru, bilva, indrayava, root of chitraka, pāthā, ativishā and liquorice;
— Charaka Samhita, Chikitsa Sthana — Therapeutic Principles, Chapter 12: Edema Treatment (Shvayathu Chikitsa / श्वयथुचिकित्सा)
Make paste of 10 gm each of chitraka, coriander, ajawan, cumin, sauvarchala-salt, trikatu, amlavetasa, bilva, pomegranate, yavakṣāra, pippalimula and chavya;
— Charaka Samhita, Chikitsa Sthana — Therapeutic Principles, Chapter 12: Edema Treatment (Shvayathu Chikitsa / श्वयथुचिकित्सा)
Take 5 gm each of jivanti, cumin, saṭi, pushkarmula, karvi (celery), chitraka, bilva and yavakashara, make a medicated gruel (yavāgu) and then fry it in ghee and oil.
— Charaka Samhita, Chikitsa Sthana — Therapeutic Principles, Chapter 12: Edema Treatment (Shvayathu Chikitsa / श्वयथुचिकित्सा)
Source: Charaka Samhita, Sharira Sthana — Human Body & Embryology, Chapter 8: Guidelines for Lineage (Jatisutriya Sharira / जातिसूत्रीय शरीर); Chikitsa Sthana — Therapeutic Principles, Chapter 11: Chest Injury and Emaciation Treatment (Kshatakshina Chikitsa / क्षतक्षीणचिकित्सा); Chikitsa Sthana — Therapeutic Principles, Chapter 12: Edema Treatment (Shvayathu Chikitsa / श्वयथुचिकित्सा)
Two Shuktis make one Pala (~48g), also called Mushti, Ama, Chaturthika, Prakuncha, Shodashi, or Bilva.
— Sharangadhara Samhita, Purva Khanda, Chapter 1: Paribhashakathana (Definitions)
Masha, Tanka, Bilva, Kudava, Prastha, Adhaka, Rashi (Drona), Goni (Droni), and Khari — each successive unit is four times the preceding one.
— Sharangadhara Samhita, Purva Khanda, Chapter 1: Paribhashakathana (Definitions)
Amritottara Kvatha: Guduchi (Tinospora cordifolia), Nimba bark (Azadirachta indica), Bilva bark (Aegle marmelos), Padmaka (Prunus cerasoides), and Raktachandana (red sandalwood — Pterocarpus santalinus) — this decoction should be consumed.
— Sharangadhara Samhita, Madhyama Khanda, Chapter 1: Svarasadikalpana (Svarasa, Kalka, Kvatha, etc.)
The ingredients are: Patala (Stereospermum suaveolens), Aranikas (Premna mucronata and Clerodendrum phlomidis), Kashmarya (Gmelina arborea), Bilva (Aegle marmelos), Araluka (Ailanthus excelsa), Gambhari (Gmelina arborea), the two Brihatis — Brihati (Solanum indicum) and Kantakari (Solanum surattense), Pippali (Piper longum), Shringi (Pistacia integerrima), Draksha (Vitis vinifera), Amrita/Guduchi (Tinospora cordifolia), and Abhaya/Haritaki (Terminalia chebula).
— Sharangadhara Samhita, Madhyama Khanda, Chapter 8: Avalehakalpana (Confection/Electuary Preparations)
The powders to add are: Rasanjana (extract of Berberis aristata), Mocharasa (Bombax ceiba gum resin), Trikatu — Shunthi (Zingiber officinale), Maricha (Piper nigrum), Pippali (Piper longum) — Triphala — Haritaki (Terminalia chebula), Bibhitaka (Terminalia bellirica), Amalaki (Emblica officinalis) — Lajjalu (Mimosa pudica), Chitraka (Plumbago zeylanica), Patha (Cissampelos pareira), Bilva (Aegle marmelos), Indrayava (Holarrhena antidysenterica seeds), and Tvak (Cinnamomum zeylanicum).
— Sharangadhara Samhita, Madhyama Khanda, Chapter 8: Avalehakalpana (Confection/Electuary Preparations)
Source: Sharangadhara Samhita, Purva Khanda, Chapter 1: Paribhashakathana (Definitions); Madhyama Khanda, Chapter 1: Svarasadikalpana (Svarasa, Kalka, Kvatha, etc.); Madhyama Khanda, Chapter 8: Avalehakalpana (Confection/Electuary Preparations)
Perform oblations with sticks of Khadira (Acacia catechu), Palasha (Butea monosperma), Devadaru (Cedrus deodara), and Bilva (Aegle marmelos) — or of Nyagrodha (Ficus benghalensis), Udumbara (Ficus racemosa), Ashvattha (Ficus religiosa), and Madhuka (Madhuca longifolia) — smeared with curd, honey, and ghee, while reciting the Pranava (Om) and Maha-vyahritis.
— Sushruta Samhita, Sutra Sthana, Chapter 2: Shishyopanayaniya Adhyaya - Initiation of the Student
Kutannata, sphotaphala, jjaka, bilva (bael), pattura, arka (calotropis), kapittha (wood apple), and bhanga (hemp).
— Sushruta Samhita, Uttara Tantra, Chapter 11: Kaphabhishyanda Pratishedha Adhyaya (Chapter on Treatment of Kapha-type Conjunctivitis)
Also ajaka, sphotaka, kapittha (wood apple), bilva (bael), nirgundi (vitex), and jasmine flowers.
— Sushruta Samhita, Uttara Tantra, Chapter 11: Kaphabhishyanda Pratishedha Adhyaya (Chapter on Treatment of Kapha-type Conjunctivitis)
Prepared from patali, arjuna, shriparni, dhataki, dhatri (amla), and bilva (bael).
— Sushruta Samhita, Uttara Tantra, Chapter 12: Raktabhishyanda Pratishedha Adhyaya (Chapter on Treatment of Blood-type Conjunctivitis)
Bilva (Aegle marmelos), Shirisha (Albizia lebbeck), Golomi, and the Surasa (basil) group of herbs should be used for sprinkling (parisheka) to pacify Skanda-type epilepsy.
— Sushruta Samhita, Uttara Tantra, Chapter 29: Skandapasmarapratishedha
Source: Sushruta Samhita, Sutra Sthana, Chapter 2: Shishyopanayaniya Adhyaya - Initiation of the Student; Uttara Tantra, Chapter 11: Kaphabhishyanda Pratishedha Adhyaya (Chapter on Treatment of Kapha-type Conjunctivitis); Uttara Tantra, Chapter 12: Raktabhishyanda Pratishedha Adhyaya (Chapter on Treatment of Blood-type Conjunctivitis); Uttara Tantra, Chapter 29: Skandapasmarapratishedha
Medical Disclaimer: The information on this page is for educational purposes only and is not intended as medical advice. Ayurvedic treatments should be pursued under the guidance of a qualified practitioner (BAMS/MD Ayurveda). Always consult your healthcare provider before starting any new treatment. Content is sourced from classical Ayurvedic texts and may not reflect the latest medical research.