The honest answer: post to both, but understand they reward different things, and your strategy should account for that instead of treating them as identical.
TikTok's algorithm is more willing to push a small account's content to a large audience quickly, based purely on video performance. Instagram Reels leans more heavily on your existing network and account history before pushing content wide.
If you're starting from zero, TikTok often shows faster initial traction. If you already have an engaged following on Instagram, Reels can convert that existing trust into growth faster than starting fresh on TikTok.
The best-performing accounts in 2026 aren't choosing one platform — they're repurposing core content across both, adjusting the hook and pacing slightly for each audience.
Whichever platform you prioritize, the same rule applies: strong content still needs a reach boost to escape the initial small-audience test phase both algorithms run new content through.
Skip the trial and error — let Dr Boost USA handle the growth side while you focus on content.