Shidou

What is SP17?

SP17 (Shidou) is a Spleen-channel point on the side of the chest, in the fifth rib space, well out towards the side of the body.

The pinyin name Shidou is usually translated as Food Cavity or Food Hole. It is the seventeenth of the twenty-one points on the Spleen channel, a channel that starts at the big toe, runs up the inner leg and abdomen, and finishes with a short run of points across the upper chest.

Classical sources group SP17 with its chest neighbours and link it to a heavy, full feeling in the chest and belly, rumbling guts, and the sense that food is sitting undigested. Because of its name, modern popular articles often present it as a digestion point.

The honest verdict on the evidence: there is essentially nothing. We found no human trial that tested SP17 on its own for digestion or for anything else. Acupressure research as a whole is mostly small, unblinded and short-term, and even that thin literature has largely ignored this point.

Two things are worth saying once, here, and not repeating in every section below. First, a point being ancient and taught in every channel chart is not evidence that pressing it does anything. Second, tradition is not a safety record either. SP17 sits over thin rib bone and close to breast tissue, so the safety side genuinely matters for this one.

What SP17 can reasonably be: a gentle, self-applied comfort measure. Slow pressure on the chest wall paired with slow breathing feels calming to many people, and that is a fair reason to use it. It is not a treatment for a digestive disease, and it is never the right answer for chest pain you have not had checked.

Where is SP17 and how do you find it?

SP17 sits in the fifth intercostal space — the soft gap one rib below the nipple level — roughly 6 cun from the midline of the breastbone, out towards your side.

• Start at the breastbone ridge. Run a finger down from the notch at the top of your breastbone. About 5 cm down you feel a small horizontal ridge; the rib joining there is the second rib.
• Walk down the rib spaces. The hollow just below that rib is the second intercostal space. Step your finger down space by space until you reach the fifth.
• Cross-check with the nipple line. In most men the nipple sits in the fourth space, so SP17 is one gap lower. In women the nipple is an unreliable landmark, so trust the rib count.
• Measure outwards. Nipple to nipple is counted as 8 cun, so the nipple line is 4 cun from the midline. SP17 is about 2 cun further out — roughly two thumb-widths, or 4 to 5 cm — towards the side of the chest.
• Land in the hollow, not on bone. Slide your fingertip up and down a few millimetres. You want the soft dip between two ribs, where the tissue gives slightly.
• Remember it is on both sides. SP17 exists left and right; treat them the same way.

On most adults this puts SP17 on the lower outer chest wall, below and to the side of the breast, roughly in line with the front edge of the armpit. Do not expect a dramatic feeling. A mild, slightly tender ache in the gap is the usual report.

If the only way to reach the spot is by pressing through breast tissue, skip the point entirely. Work from the outer edge of the chest wall instead, or choose a different point.

How do you apply pressure to SP17?

1. Sit upright and warm your hands. Cold fingers make the chest wall tense, and tense muscle hides the rib gap you are aiming for.
2. Use a flat fingerpad. The pad of the index or middle finger is right. No knuckles, no fingernails, no massage tools and nothing that breaks the skin.
3. Settle into the gap first. Confirm you are in the soft space between two ribs before you add any force. Bone under the pad means move a few millimetres.
4. Build pressure slowly. Aim for about 3 out of 10 — firm enough to feel a dull ache, never sharp. The ribs are thin out here, so heavy pressure is not more effective, just riskier.
5. Hold and breathe. Keep the pressure steady for 30 to 60 seconds while breathing slowly, then release over a couple of seconds rather than lifting off suddenly.
6. Repeat a few rounds. Two or three holds per side, once or twice a day, is plenty. Then leave it alone and see how you feel over a week.

Who should avoid it

• Anyone with new or unexplained chest pain. Do not press SP17 instead of seeking help for chest pain, pressure or tightness — get urgent medical assessment.
• Injured or inflamed ribs. Avoid SP17 on a side with a cracked, bruised or recently fractured rib, or an active costochondritis flare.
• Breast tissue and breast conditions. Do not press over breast tissue, implants, an unchecked lump, or an area being treated for mastitis.
• Recent surgery or devices. Never press over a fresh scar, chest drain site, pacemaker, port or any implanted device.
• Fragile bone. Avoid firm pressure if you have osteoporosis, bone cancer or are on long-term steroids, as ribs can break under modest force.
• Damaged skin. Do not press over broken skin, burns, shingles rash, or a mole you have not had looked at.

When to see a doctor

Stop at once if pressure causes sharp pain, breathlessness, coughing, dizziness or palpitations. Book an appointment for chest pain, trouble swallowing, unexplained weight loss, vomiting, or bloating that lasts more than two weeks.

What is SP17 traditionally used for?

• Fullness in the chest and belly. The classical headline use: a bloated, blocked, heavy feeling through the trunk. No controlled human trial has tested SP17 for this, so it rests entirely on traditional description.
• Rumbling guts and gas. Older texts list borborygmus — audible gut gurgling — among its indications. There is no human evidence that pressing SP17 changes gut sound, gas or transit time.
• Food feeling stuck. The name Food Cavity drives most modern claims about indigestion and poor appetite. Nothing in the research literature supports or refutes it, and a persistent sense of food sticking is a symptom that needs a doctor, not a point.
• Rib-side discomfort. Tradition links it to pain and distension along the lower ribs. Gentle pressure on a tender chest-wall spot can feel briefly easing, but that is ordinary soft-tissue comfort rather than a point-specific effect.
• Cough and tight breathing. Some texts include chest oppression and cough. There is no trial evidence for SP17 here, and breathing problems should be assessed properly rather than self-managed.
• Swelling and fluid retention. A few sources mention oedema (fluid swelling in the tissues). This is a traditional theory claim with no human data behind it, and new swelling is a reason to see a clinician.

For contrast, it helps to know what a well-supported acupressure claim looks like. PC6 on the inner wrist has repeated controlled trials behind it for nausea and vomiting, including in pregnancy and after surgery. SP17 has nothing of that kind.

So the fair summary is this: SP17 is traditionally a digestive and chest-fullness point, and it may be a pleasant self-care habit. Treat any specific promise about digestion as untested.

Are there tips for using SP17 effectively?

• Count ribs, do not guess. Finding the second rib at the breastbone ridge and walking down takes fifteen seconds and is far more reliable than eyeballing the nipple line.
• Press on the out-breath. Letting pressure deepen slightly as you exhale keeps the chest wall soft and makes the rib gap easier to settle into.
• Approach from the side. Lying on your back with the arm raised overhead opens the rib spaces and lets you reach the outer chest wall without pressing across breast tissue.
• Keep it light on a bony chest. If you can feel the ribs sharply under your fingers, use less force, not more. Comfort is the correct dose here.
• Give it a fair, bounded trial. Try it for a week or two and note bloating, appetite and comfort in a few words a day. If nothing shifts, drop it rather than drifting on out of habit.
• Pair it with the boring basics. Meal timing, portion size, fibre, caffeine and alcohol move digestive symptoms far more than any point does. Use SP17 alongside those, not instead.
• Keep nails short. A long nail turns steady pressure into a digging point and can nick skin over a rib.
• Skip it when unwell in the chest. On a day with a chesty cough, rib pain or a recent knock, leave the area alone entirely.

One general point about expectations. Much of the relief people report from self-applied pressure comes from pausing, breathing slowly and paying attention to the body. That is real and worth having, but it is not specific to SP17.

If you want a point with better human evidence for a related complaint, PC6 on the inner forearm is the one to read about for nausea. SP17 is best approached as tradition you are trying, not a technique you are relying on.

What do people get wrong with SP17?

• Expecting a cure. The commonest error. SP17 will not resolve reflux, irritable bowel syndrome, gallbladder disease or a hernia, and treating it as a fix delays proper diagnosis.
• Pressing on the rib. Landing on hard bone instead of the soft gap between ribs. It hurts, it bruises, and it is not the point.
• Pressing through breast tissue. Many videos show a hand planted on the breast. Work at the outer chest wall, or skip the point.
• Confusing it with its neighbours. SP16 sits on the upper abdomen, SP18 is one rib space higher, and SP21 is further round on the side under the arm. One rib space of drift puts you on a different point.
• Going too hard. Force does not improve results and the lower ribs are easy to bruise, especially in older or thin people.
• Ignoring chest pain. Using SP17 to settle chest tightness is genuinely risky. Chest pain, pressure or breathlessness needs urgent medical assessment, not acupressure.
• Copying needling videos. Clips of practitioners needling the point are not instructions for home. Self-applied finger pressure is the only safe version, with no tools and nothing that breaks skin.
• Trusting the name too much. Food Cavity is a poetic classical label, not a description of a digestive mechanism, and it should not be read as proof the point affects digestion.

A quieter mistake is inconsistency. People press once, feel nothing, and conclude the point is useless, or press daily for months without ever checking whether anything changed. Either way there is no information gained.

Set a short trial, write down what you notice, and judge it honestly at the end.

What does the research on SP17 actually say?

There is no useful human research on SP17. We could not identify a single published controlled trial that tested this point, alone or as the main point in a formula, for digestion, bloating, cough or anything else.

This is not unusual. Trial work on the Spleen channel has concentrated almost entirely on SP6 on the inner ankle and, from the neighbouring Stomach channel, ST36 below the knee. The chest points of the Spleen channel, SP17 included, simply have not been studied.

It is worth naming the comparison. PC6 on the inner wrist has repeated randomised controlled trials, plus systematic reviews, supporting a modest effect on nausea and vomiting after surgery and in pregnancy. That is roughly the strongest evidence any acupressure point has. SP17 is at the opposite end of that scale, with essentially nothing.

Where acupressure trials do exist, they share known weaknesses. They are usually small, often unblinded, frequently compare against no treatment rather than a convincing sham, and measure only short-term outcomes. Findings from such studies, even positive ones, cannot be transferred to an untested point like SP17.

What does the absence mean in practice? Not that SP17 is harmful, and not that it is useless. It means nobody has checked. Any confident claim you read about SP17 improving digestion is drawn from classical texts and clinical tradition, not from measurement.

A sensible way to handle that: treat SP17 as a low-cost self-care habit with an unknown effect, keep the pressure gentle because of the ribs underneath, and keep investigating real digestive or chest symptoms through a doctor. If decent research on this point appears, this page will say so.