REN-06 (Qi Hai) Sea of Qi

What does REN-06 Qi Hai do?

Qi Hai REN-06 is the principal qi-tonifying point of the lower abdomen and one of the two or three most-used moxibustion points in the entire repertoire. Sacred Lotus sources & references record its first action as fostering original qi — the constitutional qi the tradition places below the navel — and everything else it does follows from that. It is the point reached for when a person is simply depleted: exhausted, cold, weak-voiced, with no reserve.

• Fosters original qi (yuan qi) — the defining action. In classical theory the original qi is stored between the Kidneys and gathers in the lower abdomen, and REN-06 is the surface point where it is said to be reachable. This is why the point is used for constitutional deficiency rather than for any single symptom.
• Tonifies qi — for general qi deficiency: fatigue, shortness of breath on exertion, a weak voice, poor appetite, and the sinking, bearing-down sensations the tradition attributes to qi that can no longer hold things in place.
• Tonifies the Kidneys and fortifies yang — for cold in the lower body, aching weak lower back and knees, frequent pale urination, and the reproductive complaints classically attributed to depleted Kidney yang.
• Rescues collapse of yang — the emergency action recorded in the classical texts, for sudden collapse with cold limbs and a faint pulse. In this use REN-06 is treated with strong moxibustion rather than needled, usually alongside Guan Yuan REN-04 and Shen Que REN-08.
• Regulates qi and harmonises blood — for the lower abdomen itself: distension and pain, irregular or painful menstruation, and the qi stagnation the tradition sees behind them.

Source: Sacred Lotus sources & references (existing action record); Deadman & Al-Khafaji, A Manual of Acupuncture (p. 504); Chinese Acupuncture & Moxibustion (p. 237); cross-referenced against multiple online sources.

What is REN-06 Qi Hai used for?

Qi Hai REN-06 is used for depletion — fatigue and weakness, cold and weak lower body, and the abdominal, urinary and menstrual complaints attributed to deficient qi and yang. The indications below are those carried in Sacred Lotus sources & references together with those set out in the standard reference literature. They describe traditional use, not proven treatment, and this point carries the pregnancy and depth cautions set out under needling.

• Abdominal pain and distension below the navel
• Fatigue, exhaustion and general weakness
• Enuresis and frequent or difficult urination
• Nocturnal emission and impotence
• Hernia and dragging pain in the lower abdomen
• Oedema
• Diarrhoea and dysentery
• Constipation
• Irregular menstruation, dysmenorrhoea and amenorrhoea
• Uterine bleeding and postpartum haemorrhage
• Morbid leukorrhoea
• Flaccid-type apoplexy and collapse
• Asthma and shortness of breath on exertion

Source: Sacred Lotus sources & references (existing indication record); Deadman & Al-Khafaji, A Manual of Acupuncture (p. 504); Chinese Acupuncture & Moxibustion (p. 237).

Where is REN-06 Qi Hai, and how is it used in practice?

Qi Hai sits on the front midline of the lower abdomen, one and a half cun below the navel — a little over a finger's breadth and a half below the umbilicus, and about three and a half cun above the pubic bone. Sacred Lotus sources & references give both measurements. It is the first of the run of lower Conception Vessel points that the tradition treats as the body's qi reservoir, with Shi Men REN-05 and Guan Yuan REN-04 following it downward at half-cun and one-cun intervals.

In practice REN-06 is as often moxa'd as needled. Its most characteristic use is not to treat a named disease at all but to build a depleted person back up over a course of treatments, which is why it appears in tonifying prescriptions across almost every chapter of the clinical literature.

Which points is REN-06 combined with?

• With Zu San Li ST-36 — the classic qi-tonifying pair, and the combination with the longest documented history. A study of the acupuncture case records in the fourteenth-century Weisheng Baojian ("Treasures on Health") found the Qihai CV-6 and Zusanli ST-36 combination used widely by its author Luo Tianyi, who reached for it from the perspective of the spleen-and-stomach doctrine rather than from any direct point-to-organ correspondence — a reminder that the same pairing has been justified in different ways across the tradition (Zhongguo Zhen Jiu 2025;45(3):397–404, PMID 40097228).
• With Guan Yuan REN-04 — the two great lower-abdominal tonification points, used together for deep constitutional deficiency and, in the classical emergency prescriptions, with strong moxibustion for collapse of yang. REN-04, the Front-Mu point of the Small Intestine, is weighted more toward the Kidneys, essence and the uterus; REN-06 more toward qi itself.
• With Shen Que REN-08 — the navel, treated with moxa over salt rather than needled, in the same collapse and severe-cold prescriptions.
• With Pi Shu BL-20 and Wei Shu BL-21 — the Spleen and Stomach Back-Shu points, where the qi deficiency is traced to weak digestion.
• With Tian Shu ST-25 and Shang Ju Xu ST-37 — the standard abdominal combination for the bowels; herb-partitioned moxibustion at Qihai CV-6 with bilateral Tianshu ST-25 and Shangjuxu ST-37 is the protocol used in the published ulcerative-colitis work, and Qihai CV-6 with Tianshu ST-25 is the pairing used in the irritable-bowel and Crohn's studies.
• With San Yin Jiao SP-06 — for menstrual and reproductive complaints, adding the meeting point of the three leg yin channels to the abdominal point.
• With Qi Hai Shu BL-24 — its own back counterpart. Sacred Lotus sources & references hold BL-24 under the name Qi Hai Shu, "Sea of Qi Shu", at the level of the third lumbar vertebra; front-and-back pairing of the two is a standard structure for the lower burner.

Where does REN-06 sit among its category peers?

REN-06 carries no five-shu, yuan, luo, xi-cleft, back-shu, front-mu or confluent classification in Sacred Lotus sources & references, and none has been invented for it here. Its standing rests on function and on the weight of clinical use rather than on a category label — which is unusual for a point of this importance. Where its neighbours are classified, they are classified as Front-Mu points: Shi Men REN-05 is the Front-Mu of the San Jiao, Guan Yuan REN-04 of the Small Intestine and Zhong Ji REN-03 of the Bladder. REN-06 sits among them without one, and is nonetheless the one most often reached for.

Source: Sacred Lotus sources & references (REN-06 record; REN-03, REN-04, REN-05, REN-08 and BL-24 records queried directly); Deadman & Al-Khafaji, A Manual of Acupuncture (p. 504); Chinese Acupuncture & Moxibustion (p. 237); PMID 40097228; cross-referenced against multiple online sources.

Where is REN-06 located?

• A Manual of Acupuncture (p. 504): On the midline of the lower abdomen, 1.5 cun inferior to the umbilicus and 3.5 cun superior to the pubic symphysis.
• Chinese Acupuncture and Moxibustion (p. 237): On the anterior midline, 1.5 cun below the umbilicus.

How is REN-06 Qi Hai needled, and is it contraindicated in pregnancy?

Two things must be stated before anything else. First: Sacred Lotus sources & references carry an explicit caution that great care is required when needling the Conception Vessel points from Qu Gu REN-02 up to Shang Wan REN-13 in pregnant women — a range that includes REN-06 — and the standard reference literature lists REN-06 among the points contraindicated in pregnancy. Second: REN-06 lies over the lower abdominal cavity, where the depth recorded in the texts is bounded and the bladder is the structure immediately behind the point when it is full. Everything below is recorded as neutral reference data describing what the textbooks state. It is not instruction, and this page does not teach technique. Needling is carried out only by a qualified, licensed practitioner.

The angle and depth the texts record

• Sacred Lotus sources & references record perpendicular insertion of 0.8 to 1.2 inch, note that this is one of the important points for tonification, and record moxibustion as applicable.
• Deadman & Al-Khafaji (p. 504) and Chinese Acupuncture & Moxibustion (p. 237) record a comparable perpendicular range, and both note that oblique insertion directed downward is used where the intention is to reach the lower burner and the genito-urinary region.
• Moxibustion is the technique this point is most associated with. The reference literature records direct and indirect moxa, moxa on ginger and warm-needle technique at REN-06, and in the classical tonification and collapse prescriptions moxa rather than needling is what is described.
• The bladder. The reference literature records that the lower abdominal points are needled with the bladder empty, because a full bladder rises out of the pelvis and lies directly behind them. This is a standard recorded caution for the whole REN-02 to REN-06 group, not a hazard peculiar to this point.

The pregnancy caution, stated precisely

There are two levels to this and they should not be blurred together.

• What our own record says. Sacred Lotus sources & references carry, on this point, the caution that great care should be taken when puncturing the Conception Vessel points from Qu Gu REN-02 to Shang Wan REN-13 in pregnant women. That is a caution across a range of the channel, framed as care rather than as absolute prohibition.
• What the standard reference literature says. Deadman & Al-Khafaji list REN-06 among the points contraindicated during pregnancy, in company with the other lower-abdominal Conception Vessel points, Guan Yuan REN-04 among them, and with the small classical group that includes He Gu LI-04, San Yin Jiao SP-06 and Jian Jing GB-21. The reasoning in the classical texts is that strong stimulation of the lower abdomen and of points recorded as expediting delivery may act at the wrong time.
• What the modern evidence shows. It is worth recording honestly that controlled evidence has not confirmed the harm the prohibition anticipates. A review of the scientific literature on the so-called forbidden points found no objective evidence of harm across 15 clinical trials (823 women and several thousand treatments involving one or more forbidden points), a cohort of 5,885 pregnant women, and animal work, with rates of preterm birth, miscarriage and stillbirth comparable to untreated controls (Carr DJ, Acupunct Med 2015;33(5):413–9, PMID 26362792, DOI 10.1136/acupmed-2015-010936). The honest position is the same one that applies at every forbidden point: the traditional caution is long-standing and near-universal in the texts, the controlled evidence has not borne out the specific harm, and practitioners overwhelmingly continue to observe it.

The proportion of the risk

Abdominal points do carry a documented, if rare, hazard of visceral injury when needled beyond the recorded depth. A systematic review of the Chinese case-report literature from 1956 to 2010 identified 1,038 adverse-event cases across 167 articles, with traumatic organ injury among the small number of genuinely serious events and the authors attributing them chiefly to improper technique (He W et al., J Altern Complement Med 2012;18(10):892–901, PMID 22967282). Set against that, a meta-analysis of prospective clinical studies estimated serious adverse events at roughly 1 per 10,000 patients and about 8 per million treatments (Bäumler P et al., BMJ Open 2021;11:e045961, PMID 34489268, DOI 10.1136/bmjopen-2020-045961). REN-06 is not among the points that dominate the adverse-event literature; the cautions attached to it are about pregnancy and about staying within a bounded depth, not about a hazardous local anatomy.

Source: Sacred Lotus sources & references (existing needling record, including the REN-02 to REN-13 pregnancy caution); Deadman & Al-Khafaji, A Manual of Acupuncture (p. 504); Chinese Acupuncture & Moxibustion (p. 237); PMID 26362792; PMID 22967282; PMID 34489268 — each verified resolvable and checked for retraction status before citation.

What does the name Qi Hai mean?

Qi Hai means "Sea of Qi" — qi, the vital energy, and hai, a sea. The image is of a reservoir rather than a stream: the lower abdomen as the place where qi pools and is stored, deep enough to be drawn on when the body is depleted. It is the same region the internal-arts traditions call the dantian, and the same anatomical idea underlies both. Sacred Lotus sources & references translate the name directly as Sea of Qi. The name is also, unusually, a plain statement of the point's clinical function — which is why it is one of the few point names most students remember without effort.

Is Qi Hai REN-06 one of the classical "Sea of Qi" points?

No — and this catches most people, including many who have used the point for years. The classical Four Seas scheme names a sea of qi located in the chest, and the points assigned to it are Shan Zhong REN-17 at the front, Da Zhui DU-14 and Ya Men DU-15 behind, and Ren Ying ST-09 above. Checking the point-category records held in Sacred Lotus sources & references confirms this directly: the classification "Point of the Sea of Qi" is carried on REN-17, DU-14, DU-15 and ST-09, and not on REN-06.

So the tradition uses the phrase in two senses. The Four Seas sense places the sea of qi in the chest, where gathering qi accumulates and drives breathing and the circulation of blood. The point-name sense places a reservoir of original qi below the navel and calls the point over it Qi Hai. Both are real; neither is a mistake; they simply are not the same thing. Sacred Lotus holds every point named above, on its own page. A related name adds one more layer: Qi Hai Shu BL-24, "Sea of Qi Shu", is the Bladder-channel point on the lower back at the same functional level as REN-06 and is named after it.

Is there research on REN-06 Qi Hai?

The honest answer is that there is very little research on REN-06 as a point in its own right. It is one of the most frequently used points in the clinical literature, but it is almost always one component of a multi-point protocol, and those trials measure the protocol rather than the point. Rather than present protocol trials as though they were about this point, what is available is set out for what it is:

• Point-selection analyses do establish how heavily it is used. A systematic review of acupoint selection in acupuncture for benign prostatic hyperplasia screened 270 articles, included 85, and extracted 61 acupoints; Qihai CV-6 was among the highest-frequency selections, and association-rule analysis identified Guanyuan CV-4 with Qihai CV-6 as one of the three strongest point pairings in the field (Medicine (Baltimore) 2025;104(32):e43802, PMID 40797416, PMC12338299, DOI 10.1097/MD.0000000000043802). This tells us what practitioners actually do; it is not evidence of effect.
• Digestive-tract protocols including REN-06 have been reviewed. A systematic review and network meta-analysis compared acupuncture-related therapies for ulcerative colitis, a field in which herb-partitioned moxibustion at Qihai CV-6 with Tianshu ST-25 and Shangjuxu ST-37 is a standard protocol (Front Med (Lausanne) 2025;12:1676608, PMID 41458494, DOI 10.3389/fmed.2025.1676608). Again, the unit tested is the protocol.
• The historical literature has been studied directly. The textual study of the Qihai CV-6 and Zusanli ST-36 pairing in the Weisheng Baojian case records is genuinely about this point and its most important combination, and is a good example of the historical scholarship available for well-established points (PMID 40097228). A modern methodological discussion of a needling technique built specifically around this point — "controlling Qihai to regulate blood pressure", proposed by Shi Xuemin — has also been published (Zhongguo Zhen Jiu 2017;37(8):879–882, PMID 29231351).
• One caution about the literature. A randomised trial of electroacupuncture at Zusanli ST-36, Guanyuan CV-4 and Qihai CV-6 in sepsis, published in 2022 and still widely quoted, was subsequently retracted. It is deliberately not cited here. Readers searching for research on this point will encounter it; it should not be relied on.

What is missing should be said plainly: there is no well-powered, sham-controlled randomised trial isolating REN-06 for fatigue, qi deficiency or any of its principal traditional uses, and no mechanistic human study of the point on its own. That is a real gap for a point this central.

How does REN-06 compare with the points around it?

Guan Yuan REN-04, one and a half cun lower at three cun below the navel, is REN-06's closest counterpart and the one it is most often confused with. Both are great lower-abdominal tonification points and both carry the same pregnancy and depth cautions; the working distinction is that REN-04, the Front-Mu point of the Small Intestine and a meeting point of the Conception Vessel with the Spleen, Liver and Kidney channels, is weighted toward the Kidneys, essence, the uterus and yin, while REN-06 is weighted toward qi and yang. In practice they are frequently used together rather than chosen between. Shi Men REN-05 sits between them at two cun below the navel as the Front-Mu of the San Jiao and is used far less. Zhong Ji REN-03, at four cun below the navel, is the Front-Mu of the Bladder and the point for urinary and lower genito-urinary complaints proper. Shen Que REN-08, the navel itself, is never needled and is used with moxa. Behind, Ming Men DU-04 on the midline at the second lumbar vertebra and Shen Shu BL-23, the Kidney Back-Shu point beside it, are the back-of-the-body partners for the same yang-warming intention, and Qi Hai Shu BL-24 is REN-06's direct namesake behind. Distally, Zu San Li ST-36 is the point REN-06 is paired with more often than any other.

Source: Deadman & Al-Khafaji, A Manual of Acupuncture (p. 504); Chinese Acupuncture & Moxibustion (p. 237); Sacred Lotus sources & references (REN-06 record; Sea of Qi, Front-Mu and neighbouring-point classifications queried in full); PMID 40797416 (PMC12338299); PMID 41458494; PMID 40097228; PMID 29231351 — each verified resolvable and checked for retraction status before citation; the retracted 2022 sepsis trial deliberately excluded; cross-referenced against multiple online sources.