The Sardine Fast - I'm Not Kidding

The Sardine Fast - You're Not Kidding?

Sometimes really outrageous ideas come across the news that just need a bit of digging to understand. Sardines? Let's dig in.

An Internist in South Dakota, Annette Bosworth, MD, who is a prolific Youtuber, and somehow lost her license for some of her other political activities, who goes by the name of Dr. Boz, came up with this idea in 2023. She is an advocate for the carnivore diet and supports herself selling bison liver/meat capsules for humans. Already, the source sounds a bit eccentric.

If it weren't for the over 600,000 people who have viewed her YouTube vlog on sardines, and the dozens of Hollywood personalities who have tried it, you could shake this off as too weird to take seriously. But hang in there. Consider, 10 days of sardines only. You can get mustard, curry, olive oil, black pepper, or just plain brine, but it remains just plain sardines. There aren't many people who like sardines all that much. You eat them only because you are hungry. Really hungry.

Sardines are ocean-caught fish, rich in omega-3 fats. DHA, the most common omega three fat is incredibly liquid and doesn't freeze in ice cold water. That allows many fish to thrive in freezing cold water. But grass-raised animals also are rich in omega-3 fats, until they eat artificial carbohydrates like corn and beans. Our hunter-gatherer forebears ate lots of meat, if they could get it and tended to settle in venues where they had access to meat, either animal or fish in source. The ratio of omega 3 (the healthy stuff from animals) to omega 6 (the omega fat from seeds and nuts) used to be one:one. Animals get their omega-3s from green plants or algae in water. Because our animals are feedlot raised, their content of omega-3s plummets and omega-6s rises to create a modern ratio of about 1:20. Folks who eat lots of fried food will be 1:50. The problem with omega-6 fats is that they are the precursor molecule to inflammatory cytokines, so we tilt the balance to making more inflammatory markers.

Sardines are similar to the eulachon fish of the Pacific Northwest. The First Peoples of the Northwest used to harvest it, dry it in the sun, and make cakes of it that they traded far and wide. Called the Oolichan, it actually had less omega-3s and more saturated fat. It was called the candlefish because it would burn when lit. The Innuit of Alaska sought out seals and walruses for their blubber, which was much higher in omega-three fats.

Sardines have about 2 grams of DHA for each 3 oz can. That's about as high a food source as any other fish. When you eat the "sardine diet, or sardine fast" you are getting the majority of your calories from omega three fats. You are eating an Innuit diet. Early descriptions of the Innuit didn't include obesity. Modern Innuit eat 20 times the omega-3 fats because they still catch ocean fish and an occasional seal. But they have added sugar and flour in their trade with "outsiders" and have developed obesity. Interestingly enough, with their high intake of fish oil, and omega-3 fats, they have not developed the level of diabetes of other First Peoples. There is something protective about that high omega-3 fat diet.

But back to our sardine diet. One 3.5-ounce can is only 191 calories. Two cans is 382 calories. And you feel stuffed. Get the drift? Fifty percent of your calories will be from fat, and that's omega-3 fats. Three meals a day of omega three fats and you are getting 6 grams a day of omega three fats, but only 1100 calories.

You are getting no carbs or glucose source so your body has to switch to fat burning. It takes a day or so to get there so the first day may feel a bit rough as your peroxisomes gear up to burn fat. But once you are burning fat, it doesn't matter where you get it from. Sardines? Your own fat stores?

That's the 10-day sardine challenge. Not everyone makes it. That may happen in part because your partner may want nothing to do with you for those 10 days. But you will be in ketosis, and you will lose weight. You can feel a kinship with the First Peoples of the Pacific Northwest or the Innuit of Alaska.

www.What will Work for me? I haven't done this experiment. Not sure I ever will. I wanted to read the details. I suspect there is a nugget of truth in it. Our bodies were tuned to getting more omega-3 fats in their food chain. That's just another element that disappeared in our industrial; food system. There are clues that we really need more omega-3 fats back. Preferably from natural, real-world sources. Pills just don't provide the same benefit. This idea may have legs (or is it fins?). Maybe we really do need more DHA.

References: Slate, BMC Research Notes, McGill U, Frontiers in Nutrition, Science Daily, Eat This Much,

Pop Quiz

1. What is an omega-3 fat?                         Answer. It is a polyunsaturated fat with the first double bond on the 3rd carbon in the long chain. EPA is 20 carbons long with 4 double bonds. DHA is 22 carbons long with 5 double bonds. DHA is is critical component of plasmalogens, giving them their fluidity and flexibility. DHA is also a precursor molecule for many anti-inflammatory compounds.

2. Where does DHA come from?                          Answer: Green plants only. Algae in the ocean, and grasses and green leaves on land. Fish eat algae, and then up the food chain.

3. Why are sardines good for you?                        Answer: They are power-packed with DHA, getting 2 grams per 3.5 ounce can.

4. So, just what is the sardine diet?                      Answer: Eating JUST SARDINES, three times a day. Or whenever you feel hungry. Which you won't. 

5. What happens to your body?                          Answer: You end up only eating 1000 calories a day because you just don't feel hungry. You get into ketosis and you lose weight. Something spooky about all that DHA. We used to have it in our food chain when our animals were raised on grass and in just the last 100 years, it got deleted, inadvertently, when all our animals were moved to feed lots.