Ask a room of POTS patients what symptom they would trade away first and most will not say the racing heart. They will say the fatigue: the bone-deep, sleep-doesn’t-fix-it kind that turns a flight of stairs into an afternoon. So it is worth knowing that the most famous experiment on fatigue in the nutrition literature is seventy-five years old, has never been explained, and points away from the vitamin bottles most POTS patients are told to buy.
The 1951 swim test
Benjamin Ershoff, a nutrition researcher in Los Angeles, raised three groups of rats from weaning. The first ate a purified diet with all eleven vitamins known at the time. The second ate the same diet plus the whole B-complex. The third ate the same diet with 10 percent of it replaced by dried liver. Then he put them in 20°C water and timed how long they could swim.
The vitamin rats quit at 13.3 minutes. The extra-B-vitamin rats quit at 13.4 minutes: every B vitamin known, and it bought them six seconds. The liver rats swam 63, 83 and 87 minutes on average, and nine of twelve were still going when he ended the test at two hours.
Ershoff named the missing ingredient the “anti-fatigue factor.” Nobody has isolated it since.
Why this matters more in POTS than almost anywhere
Low iron stores and low B12 turn up again and again in people with POTS, and both are classic fatigue drivers, so patients are routinely handed an iron tablet and a B12 or B-complex. Some feel better. Many don’t, and the swim test hints at why. The iron in liver comes with the copper needed to use it. The B12 comes with folate and the other B vitamins in forms the body already recognizes, plus CoQ10, heme and cofactors that still don’t have names. A tablet delivers one molecule, in a dose someone guessed at, and asks your body to supply the rest.
Skeptics say Ershoff’s control diet was simply iron-poor and liver corrected it. Perhaps that was part of it. But no one ever reproduced the result by adding iron to the vitamin list, and I think the reason is that the anti-fatigue factor is not a factor at all. It is synergy, nutrients arriving together in the ratios nature worked out before we started counting. The best science of 1951 built a “complete” diet and left out what it didn’t understand. We are still doing that.
There is a second reason isolated vitamins deserve caution. When the dose guess is wrong you get the excess too. Recent research on megadosed niacin and NAD boosters found the leftover metabolite (4PY) inflames the lining of blood vessels, and inflammation is not something a POTS patient needs more of.
What I use in my POTS protocols instead
This is why the supplements in my plans are whole-food based, and why they are the ones they are.
Kickstart My Heart is freeze-dried New Zealand elk liver, heart and kidney. Liver is exactly what Ershoff’s rats got: heme iron with its copper, B12 with its folate, and the rest of the B-complex in food form. Heart adds CoQ10 and the mitochondrial cofactors that matter when the complaint is “no energy.” For many of my POTS patients it replaces an iron pill, a B-complex and a CoQ10 capsule.
Wild Salmon Roe supplies methylated B vitamins, omega-3s and choline in their natural forms and ratios, rather than three separate bottles.
Shilajit resin covers the trace minerals and fulvic acid no label has ever itemized. POTS patients are told, correctly, to push sodium and fluids; the trace minerals that ride alongside sodium in whole foods are the part that usually gets forgotten.
Three things, fewer bottles, and all of what the 1951 rats were missing, including the parts nobody has named yet. None of this replaces the fundamentals of POTS care: fluids, salt, compression, graded recumbent exercise, sleep, and finding the root cause driving the dysautonomia in the first place. But if the fatigue has not budged on a shelf of synthetic vitamins, the rats suggest where to look next.
I go into the experiment in more depth on BestHeartBeat.com. For a personalized look at your own supplement list, labs and POTS plan, I offer telehealth consults through Natural Heart Doctor.
Source: Ershoff BH. Beneficial effects of liver feeding on swimming capacity of rats in cold water. Proc Soc Exp Biol Med 1951;77:488–491. Educational content, not individual medical advice; discuss any supplement change with your own physician.
