Are you boiling away your gains? 💦💨

Somewhere in the last decade, raw food got a reputation as the pure, untouched, nutritionally superior way to eat, and cooking got cast as the villain that murders your vitamins on a hot stove. It's a tidy story. It's also, for a lot of vegetables, flat-out wrong. See what the newest research has to say 👀 

The carrot that exploded its value in the oven

A 2026 study out of the University of Seville ran tomatoes and carrots through the whole appliance lineup — oven, microwave, air fryer — and measured how much of their carotenoids (the pigment compounds your body converts into vitamin A) actually survived digestion in a form you could absorb. In raw carrots, the supposed gold standard, most of those carotenoids stay trapped behind cell walls too tough for your digestion to crack. Roast the carrots in the oven and the absorbable amount jumped roughly ninefold. Not nine percent. Ninefold.

Tomatoes showed the same pattern — air frying or baking bumped up their usable carotenoids about 1.5 times over raw. The heat breaks down the rigid plant structure that keeps those nutrients locked away, which is the opposite of the destruction the raw-food crowd keeps warning about. Your perfectly nice raw salad is, in some cases, a lockbox you forgot to open.

Spinach, unlike revenge, is a dish best served hot

Raw spinach comes packed with oxalates, natural compounds that bind to the iron and calcium in the leaf and keep them from being absorbed. A little heat breaks those oxalates down and frees the minerals up, which is why a pan of sautéed spinach delivers more usable iron than the same volume raw — an annoying fact for anyone who has been smugly blending raw spinach into smoothies as a power move.

Before you deep-fry everything in triumph

Cooking isn't the universal hero either, because that would be too simple and nutrition is never allowed to be simple. Vitamin C and a broccoli compound called sulforaphane — one of the more impressive anti-inflammatory things you can eat — are both wrecked by heat. Raw or barely-steamed broccoli, cabbage, and bell peppers hold onto far more of the good stuff than their well-done versions. So the leafy cruciferous crew and your vitamin-C vegetables want a gentle touch, while carrots, tomatoes, and spinach want the heat.

Broccoli in particular comes with a free trick worth knowing. Sulforaphane doesn't exist in the florets until an enzyme gets activated by damage — chopping or chewing — and that enzyme is destroyed by heat before it finishes the job if you cook right away. A study in the Journal of Agricultural and Food Chemistry found the fix is to chop your broccoli into small pieces and then let it sit for around 40 minutes before cooking, which gives the enzyme time to do its work before the heat arrives. It's the rare health tip whose main instruction is "do nothing for 40 minutes."

And there's one method that loses almost no matter what you put in it: boiling. Drowning vegetables in hot water gives their water-soluble vitamins a convenient escape route straight into the cooking liquid, which you then pour down the sink. One test found boiling stripped carrots of their polyphenols completely — zero left. If you've been boiling your vegetables into gray submission and wondering why they taste like warm nothing, the nutrients left the same way the flavor did.

The frozen aisle’s redemption

Frozen vegetables have spent years treated as the lesser option, the thing you settle for when you didn't make it to the farmers market. The research says that reputation is unearned. A study in the Journal of Agricultural and Food Chemistry compared eight fresh and frozen fruits and vegetables and found the frozen versions were nutritionally comparable to fresh, and in several cases higher — vitamin C actually came out ahead in frozen for a number of them. The reason is timing: produce headed for the freezer is usually picked at peak ripeness and frozen within hours, while "fresh" produce can spend a week or more in trucks, warehouses, and your crisper drawer slowly shedding vitamins the entire way. The one asterisk is that long freezer storage can wear down beta-carotene in some vegetables, so frozen is "as good as fresh, often better" rather than a clean sweep. For most people, most of the time, the bag in the freezer is doing at least as well as the bunch wilting in the fridge.

What it all boils down to

Steam or roast more, boil less — that single swap saves more nutrients than any supplement you could buy to replace them. Cook your tomatoes, carrots, and spinach to unlock what they're hiding; keep your broccoli and peppers raw or lightly steamed to protect what heat would destroy. Add a little olive oil to anything colorful, because carotenoids need fat to get absorbed at all and a dry carrot is a wasted one. And stop treating raw versus cooked like a moral choice — the move that actually wins is eating both, across a lot of different plants, prepared a lot of different ways.

None of this requires a new diet or a single dollar spent. It's the same vegetables you already buy, pointed at the right appliance.

Eat the rainbow (lightly oiled),
Your West Coast Fitness Family