The Tamesis
I won’t share my husband’s exact reaction when I told him I was going to start a “sardine fast,” other than to know that it wasn’t a positive one. As someone who is a huge fan of canned fish—anchovies, sprats, mackerel, you name it—the prospect of following instructions on the internet and eating only sardines for three days wasn’t particularly daunting to me. But I do feel for anyone who may have encountered me during this time, and as my significant other, he was directly on the shooting line (or should that be fishing?).
The sardine fast is a viral diet trend currently racking up thousands of views on TikTok. Google reports that searches for “sardines” and “Dr. Boz sardine fast” have increased by more than 5,000% in recent months. So what’s going on? Why all the fuss over such a small and inconspicuous fish?
What is a sardine fast?
A sardine fast lasts one to three days (or longer, if you prefer) and consists of eating canned sardines…and nothing else. The idea is that it lowers blood sugar, promotes rapid weight loss (allegedly due to increased ketone levels), and, most importantly, leaves your skin glowing. It was the latter side effect that convinced me to give it a try.
This most specific form of fasting has gained attention in recent months for two reasons. Dr. Annette Bosworth (also known as “Dr. Boz”), an American doctor who specializes in metabolic health, promotes it on TikTok and podcasts as a way to quickly boost ketones. Meanwhile, speaking to biohacker Tim Ferriss, metabolic therapy researcher Dr. Dominic D’Agostino claimed that his friend “Dr. Squat” went into remission from metastatic prostate cancer after a monthly, week-long sardine fast.
While they are both compelling speakers, I prefer to err on the side of caution when it comes to viral health trends. It also made me wonder if limiting one’s diet to only fish would actually be beneficial to anyone. Is this the only way to truly understand? By trying it myself.
First day of my sardine fast
It’s a dangerous day for sardines: I’m ready and craving sardines with a choice of olive oil, spring water and tomato sauce. I opened a can, placed the contents in a small bowl and heated it. I’ve seen some people eat them cold, but since I’m not really a cat person, this was too much for me.
It’s breakfast time and I love fish in the morning – usually mackerel or herring first thing. They’re a great source of protein and rich in omega-3s, especially EPA and DHA, which nutritionist Dr. Federica Amati told me are like the body’s natural anti-inflammatory drugs. “They support heart health, help balance cholesterol, and play an important role in brain function, mood, and skin appearance,” she explains. “Add high-quality protein, vitamin D, B vitamins, calcium (especially if you eat cartilage), selenium and other trace minerals. It’s a complete package.”
They also tasted great and kept me full until at least noon, when I started thinking about my next meal. Spoiler alert: more fish.
To be honest, I was starting to get a little scared. Where are the vegetables? I really wanted some carbs. Instead, I eat sardines and stay hydrated with ginger tea and water with electrolytes (I’m not good at fasting).
By night, I was grumpy, low on energy, and hungry. I treat myself to sardines in tomato sauce – which is very different from olive oil – sprinkle some salt on top and keep eating. It’s hard to eat sardines when your husband is enjoying delicious pho, but rules are rules.
