Classical hatha yoga did not begin with poses. Open the Hatha Yoga Pradipika, the 15th-century manual that anchors the tradition, and the body practices start with something modern studios quietly skip: a set of cleansing techniques called kriyas. Some of them you already know. Some of them you will be very glad nobody asks you to do in class.
The word itself
Kriya (क्रिया) comes from the root kri, "to do" or "to act" — the same root that gives us karma. It simply means action, practice, or procedure. In hatha yoga it refers specifically to the shatkarmas, the "six actions" of purification. One warning before we start: the same word also names Kriya Yoga, a specific meditation lineage (Lahiri Mahasaya, later popularized by Yogananda), and Patanjali's own three-part formula of discipline, self-study, and surrender. Same word, three different things. This page is about the cleansing practices.
The six shatkarmas
- Neti — nasal cleansing. The classic version is jala neti: warm salt water poured through the nostrils with a small spouted pot. (There is also sutra neti, threading a waxed string through the nose. The string version can stay in the 15th century.)
- Dhauti — cleansing the digestive tract, classically by swallowing and retrieving a long strip of cloth. Yes, really. Historical interest only.
- Basti — the yogic enema, originally performed standing in a river using suction. Modern colonic marketing sometimes borrows the glamour; the classical practice belongs in a museum case.
- Trataka — steady gazing at a candle flame until the eyes water, described as cleansing the eyes. This one survives, rebranded as a concentration meditation, and it's a good one.
- Nauli — isolating and churning the abdominal muscles in a rolling wave. Spectacular to watch, genuinely hard, and a serious abdominal workout with traditional claims about "massaging" digestion.
- Kapalabhati — "skull-shining breath," rapid pumping exhales. This is the one kriya every modern practitioner meets, now filed under breathwork and covered in detail on our kapalabhati page.
What modern evidence says
Sorted by how well they survived contact with contemporary understanding:
- Jala neti: genuinely useful. Saline nasal irrigation is standard advice from ENT doctors for sinus congestion and allergies, and the clinical evidence is decent. The yogis had a working practice centuries before randomized trials existed. Use distilled or previously boiled water, though — tap-water neti has caused rare but serious infections.
- Kapalabhati: real effects, honestly described. It's vigorous breathing, and it measurably wakes you up, works the respiratory muscles, and shifts the nervous system toward alertness. "Purifies the frontal brain" is poetry; "you'll feel clear and buzzy" is accurate.
- Trataka: solid as attention training. Nothing cleans your eyes except tears, but as a focus drill it's excellent.
- Nauli: impressive, optional. Fine as a core control drill for experienced practitioners; the detox claims are decorative.
- Dhauti and basti: do not. Swallowing cloth and DIY colon irrigation carry real risk — injury, infection, electrolyte problems — and no benefit you can't get from fiber and water.
Why the tradition cared so much
Step back and the shatkarmas make sense as a product of their setting. The hatha texts promise to prepare the body for meditation and, in their framework, to clear the nadis so prana can move. In a pre-modern world of dust, smoke, infections, and no antibiotics, a clean nose and a regulated gut genuinely were the difference between a functional body and a miserable one. The practices were hygiene before hygiene had a germ theory — framed, as everything was, in the language of energy.
That's also why the heavy-duty versions faded: modern sanitation and medicine simply do those jobs better. What survived — neti, trataka, kapalabhati — survived because the yoga version is still competitive with anything the pharmacy offers.
The honest part
The word "detox" gets attached to kriyas a lot, and it's worth being blunt: your liver and kidneys do your detoxing, and no breathing technique or nasal rinse substitutes for them. What the surviving kriyas actually offer is narrower and better: clearer sinuses, sharper attention, a more awake nervous system, and a small daily ritual of taking care of the machinery you sit in. That's plenty.
The shatkarmas are a reminder that yoga was always practical first — the mysticism was the packaging, not the product.