If I were to wake up tomorrow as hypothyroid as I was 10 years ago, here's what I'd do to fix it:
• Eat a warm, satiating breakfast within 40 minutes of waking (daily, no exceptions). E.g., chicken soup + orange juice.
• Eat at least 300 grams of net carbs/day, and make sure that carbohydrates are the key macro at every meal. The release of the active thyroid hormone (T3) directly corresponds to dietary carbohydrate intake. I'd focus on nutrient-dense carbs like ripe fruit (e.g., oranges, papayas, grapes, mangoes, cantaloupes), freshly-pressed orange & pomegranate juice, potatoes, squashes, and yams.
• Ditch the plant milks and switch to warm goat milk, while also becoming diligent about getting at least 1 gram of calcium/day.
• Ditch all polyunsaturated oils (e.g., canola, sunflower, soybean, rice, sesame oil), avoid fatty chicken & pork, and avoid all products that use these oils (Read labels. Most conventional pantry items, spreads, and dressings contain them).
• Ditch all raw vegetables (temporarily) and ditch all raw, cruciferous vegetables permanently (always cooking them thoroughly before eating). Goitrogens in raw crucifers mess with iodine handling.
• Stop over-training, reduce training intensity and/or frequency, and NEVER train fasted or hungry.
• NO fasting. A minimum of 3 meals per day (breakfast, lunch and dinner) + a potential bedtime snack.
• Cut out all nuts and seeds (at least temporarily).
• Eat at least 2,000 kcal/day.
• No coffee on an empty stomach.
• Warm ginger tea before every meal and in between meals for hydration.
• Cook only with coconut oil (at least temporarily)
• Get vitamin D levels up by taking 2,000 IU of vitamin D3 per day.
• Selenomethionine or SelenoExcell taken 3-4 times a week + a pinch of wakame seaweed added to broths and soups.
• Chicken liver, eaten 1-2 times per week, beef liver 1-2 times a month, and oysters 3-4 times a month for vitamins and minerals (can't make thyroid hormones without retinol, selenium, and iron).
• Cut out grains (at least temporarily), especially wheat/gluten.
• Check ferritin levels & full iron panel (to rule out an iron deficiency).
• Get as much sun as possible during the day & use red light therapy in winter.
• Warm meals (soups, stews) > salads or smoothies.
• Don't neglect sleep by staying up too late.
• Take rest seriously, don't push yourself to exhaustion.
• Get magnesium levels up with magnesium chloride spray, Epsom salt baths, & magnesium taurate or mag glycinate supplements.
• Consider taking a natural desiccated thyroid supplement for some time (to counter epigenetic memory + provide thyroid specific peptides).
• Prioritize gelatinous meats (e.g., beef cheeks, oxtail, tripe) and shellfish over chicken breast.
• Consider using small amounts of progesterone in the luteal phase.