Not all proteins are equally easy to eat on GLP-1. Red meat requires sustained chewing and can feel heavy when the stomach is slower to empty. Chicken breast, if not prepared carefully, can be dry and difficult. But white fish — and cod in particular — occupies a rare position: high protein, very low fat, extremely mild in flavor, and genuinely easy to digest even when the GI system is sensitive.

Cod has approximately 20g of protein per 100g of cooked fish, under 90 calories, and virtually no fat. The texture when properly cooked is soft and flaky — it requires almost no chewing effort and breaks apart easily. This makes it one of the few high-protein foods that works on difficult eating days as well as good ones.

Sweet potato is the natural companion. It provides slow-digesting complex carbohydrates, significant fiber (4g per medium potato), and a natural sweetness that complements the mild savory flavor of cod beautifully. Together they form a complete, balanced meal with enough carbohydrate for sustained energy and enough protein for satiety.

Why This Works on GLP-1

Cod's digestibility is its primary advantage for GLP-1 users — including those on Zepbound or Wegovy —. White fish protein is broken down quickly and gently by the digestive system — it does not sit heavily in a stomach that is already emptying more slowly due to medication. This makes it one of the best protein choices for days when GI sensitivity is elevated or appetite is uncertain.

The cooking method here — oven baking with lemon, herbs, and olive oil — preserves the moisture in the fish and prevents the dryness that makes other proteins difficult to eat. A properly baked cod fillet is almost self-saucing: the lemon juice and olive oil meld with the fish's natural juices to create a light, flavorful coating.

Sweet potato provides beta-carotene, potassium, and vitamin B6 alongside its fiber and complex carbohydrates. Unlike regular potato, sweet potato has a lower glycemic index and provides a more sustained energy release — which is particularly relevant for GLP-1 users who may not eat again for a significant period after this meal.

Ingredients (serves 2)

  • 2 cod fillets (about 180g / 6oz each)
  • 400g (14oz) sweet potato, cut into 2cm (¾ inch) cubes
  • 2 tablespoons olive oil, divided
  • 2 garlic cloves, minced
  • 1 lemon — zest and juice
  • 1 teaspoon dried thyme
  • ½ teaspoon smoked paprika
  • Salt and black pepper
  • Fresh parsley to serve (optional)

Instructions

  1. Preheat the oven to 200°C (400°F). Line a large baking sheet with parchment paper.

  2. Roast the sweet potato first. Toss the sweet potato cubes with 1 tablespoon of olive oil, ½ teaspoon smoked paprika, salt, and pepper. Spread in a single layer on the baking sheet. Roast for 15 minutes until beginning to soften and caramelize at the edges.

  3. Prepare the cod. Pat the cod fillets completely dry with paper towel — this is important for good texture. In a small bowl, mix the remaining tablespoon of olive oil with the minced garlic, lemon zest, thyme, salt, and pepper.

  4. Add the cod to the pan. After the sweet potato has had 15 minutes, push it to the sides of the baking sheet. Place the cod fillets in the center. Spoon the garlic-herb oil over each fillet. Squeeze half the lemon juice over everything.

  5. Bake. Return to the oven for 12–15 minutes. The cod is done when it flakes easily when pressed gently with a fork and is opaque all the way through. Do not overbake — dried-out cod loses its gentle, easy texture.

  6. Serve. Plate the cod alongside the sweet potato. Squeeze the remaining lemon juice over the fish and scatter fresh parsley if using.

Nutrition per Serving

  • Calories: ~370
  • Protein: ~35g
  • Fat: ~10g
  • Carbs: ~35g
  • Fiber: ~5g

Practical Notes

Pat the fish very dry. Moisture on the surface of the fish prevents it from developing any color and creates steaming rather than roasting. Dry fish = better texture and flavor.

Check doneness at 12 minutes. Cod cooks faster than most people expect. Fillets that are too thick should be scored with a knife before baking to ensure even cooking. Overcooked cod becomes dry and chalky — undercooked cod flakes imperfectly and looks translucent. The target is fully opaque, just barely resisting when pressed.

Frozen cod works well. Frozen cod fillets are often excellent quality and more affordable than fresh. Thaw overnight in the fridge or under cold running water for 15 minutes. Pat extremely dry before cooking.

Sweet potato sweetness varies. Older sweet potatoes can be less sweet. If yours are mild, add a very light drizzle of honey or maple syrup to the cubes before roasting to encourage caramelization.

Scale down easily. One cod fillet + half the sweet potato is a perfectly proportioned single meal for a day when appetite is moderate. The recipe scales down to one portion without any adjustment to cooking time.

Frequently Asked Questions

Can I use a different white fish if cod is unavailable?
Yes — haddock, pollock, tilapia, and basa are all excellent substitutes with similar protein content and a similarly mild, easy-to-digest character. Haddock in particular has a very comparable texture and flavor profile to cod. Avoid oily fish like mackerel or sardines if you are looking for the same mild, gentle eating experience this recipe delivers, as they have a significantly stronger flavor.
How do I know when the cod is cooked without a thermometer?
Press the thickest part of the fillet gently with a fork — cooked cod will flake apart in clean layers and appear opaque (white) all the way through. Undercooked cod looks translucent and feels firm and resistant. Overcooked cod becomes dry and pulls apart in a stringy rather than flaky way. The fork test is reliable and takes seconds to learn after one or two attempts.
My appetite on GLP-1 is very small — can I reduce the portion without ruining the dish?
This recipe scales down cleanly to a single serving: use one cod fillet and half the sweet potato. The cooking time does not change. On very low appetite days, even eating just the cod fillet (skipping the sweet potato or saving it for later) gives you approximately 35g of protein in a form that is easy on the stomach. The sweet potato can be eaten cold later as a snack if appetite returns.
Does frozen cod work as well as fresh, and how should I thaw it?
Frozen cod often rivals fresh in quality because fish is typically frozen within hours of catch. Thaw it overnight in the refrigerator for the best texture, or under cold running water in a sealed bag for about 15 minutes if you need it faster. The critical step after thawing is to pat the fillet very thoroughly dry with paper towels — frozen fish releases more water than fresh, and excess moisture will prevent browning and create a steamed rather than roasted texture.
What can I serve alongside this meal if I want more variety without adding too many calories?
A small green salad dressed with lemon juice and olive oil adds fiber and volume with minimal calories. Steamed broccoli or green beans also pair naturally with the lemon-herb flavors in this recipe and contribute additional fiber and micronutrients. If you need more caloric density on a day when you have managed to eat well, a tablespoon of tahini or a spoonful of Greek yogurt alongside adds protein and fat without disrupting the clean flavor of the dish.

This article provides general food and nutrition guidance only. It does not constitute medical advice. Always consult your healthcare provider regarding your GLP-1 medication and individual nutritional needs.