Ka Wai Ola - Office of Hawaiian Affairs, Volume 3, Number 6, 1 June 1986 — He Mau Ninau Ola [ARTICLE+ILLUSTRATION]

He Mau Ninau Ola

Some Heahh Questions by Kekuni Biai$dell, M,D.

Ninau: E kauka, I do not understand how salt causes my high blood pressure, because I do not get pehu (swollen). Yet, my husband gets pehu from eating too mueh pa'akai, but he does not have high blood pressure. Why the difference? Pane: Your ninau raises an important distinction between sodium in pa'akai

(salt) as a cause of arterial koko pi'i (hypertension) and sodium as a cause of pehu. 'Ano pohihihi ka wehewehe ' and (the explanation is somewhat complicated.) Habitual nui loa (too mueh) sodium-eating over years appears to raise blood pressure in sodium-sensitive kanaka by several mechanisms: • Excess sodium may alter na pu'upa'a (kidneys) so that

they retain sodium and wai (water) in the kino (body) instead of excreting the excess in the mimi (urine). • Too mueh wai in the koko fblood) enhances contraction (pumping action) of the pu'uwai (heart), with increase of the systolic blood pressure. The systolic, or contraction, pressure is the first and higher of the two blood pressure values recorded when your kauka measures your blood pressure with a cuff on your arm. • Nui loa sodium in the pa (wall) of the arterioles (small arteries) narrows these a'a (vessels) and increases their eonstricting responses to certain nerves and chemicals. This raises the diastolic pressure — the second and lower of the two blood pressure values, whieh registers when your pu'uwai is transiently relaxed between contractions. • Since 1982, experiments have demonstrated elevation of a special hormone in the koko from the lolo (brain) and the pu'uwai in hypertensive po'e (people). This natriuretic ehemieal prevents sodium movement out of cells, such as the arteriole pa a'a (vessel wa!ls), and thus, diastolic hypertension is promoted. Up to a point, all of the above mechanisms of nui loa sodium !eading to koko pi'i ean be reversed by your restricting sodium intake to less than 1 gram per day, and or by medication prescribed by your kauka that induces your pu'upa'a to excrete the excess sodium and wai from your body into your mimi.

As for sodium and pehu, the earliest recorded case in kanaka Hawai'i since foreign contact, may be that of Kalanimoku, Kamehameha's prime minister, who is said to have died in 1827 of 'opu'ohao (swelling of the abdomen) in spite of waiki enema therapy. Pehu may have numerous causes, but the commonest general forms are due to pu'uwai failure, ma'i pu'upa'a, ma'i akepa'a (liver disease), ma'i 'a'ai (cancer) and inflammation. Koko pi'i is not a cause of pehu; only when some complication or additional ma'i occurs, is pehu associated with koko pi'i. Pehu may result from multiple factors concerned with the passage of wai through the capillctry (smallest a'a) wall into the surrounding tissue. In many forms of pehu, nui loa sodium and wai are retained as a causal factor, but without koko pi'i. Your kane (husband) may be so affected. In such instances, reducing sodium intake will often, but not necessarily, relieve the pehu. Ninau: How did salt eome to be used as a food by Hawaiians and other people? Pane: Haole authorities speculate that throughout the 40 million years of human evolution, and most of the 40,000 years of "modern" man, salt as food was unknown. It was not until about 12,000 years ago, they say, with the invention of agriculture, and thus man's conversion from a mainly-meat to a part-vegetable diet, that he began to need a little supplementary sodium, and also he began to preserve food with salt. Onee he acquired an habitual "taste" for salt, his blood pressure tended to rise with his age. Thus, salt-related hypertension appeared as a "disease of civilization." Po'e Hawai'i, who first settled in the northern Pacific some 2,000 years ago, were the oniy Polynesians who collected granular salt for use from the kai (oeean) by speciallyconstructed, large, earthern kaheka (salt ponds), and by small, pohaku (rock) kahapa'akai (salt-evaporating pans). Export of pa'akai from Hawai'i to Europe became a major industry in the early 1800s. Pa'akai was used not only to preserve food (since it inhibits bacterial action) and for seasoning, but also as medication with 'alaea (ocherous earth), and thus, was endowed with special mana. Indeed, in lean tirpes, pa'akai with poi alone were sufficient to make a meal, as in the 'olelo no'eau: I komo ka 'ai i ka pa'akai. In future columns, more on koko pi'i, ka 'ai, and kekahi mau ninau loa o ka lahui Hawai'i.