diff --git a/source/index.ts b/source/index.ts
index 1cbf72c..3e72b71 100644
--- a/source/index.ts
+++ b/source/index.ts
@@ -136,7 +136,7 @@ namespace is { // tslint:disable-line:no-namespace
 	export const nullOrUndefined = (value: any): value is null | undefined => null_(value) || undefined(value);
 	export const object = (value: any): value is object => !nullOrUndefined(value) && (function_(value) || isObject(value));
 	export const iterable = (value: any): value is IterableIterator<any> => !nullOrUndefined(value) && function_(value[Symbol.iterator]);
-	export const asyncIterable = (value: any): value is AsyncIterableIterator<any> => !nullOrUndefined(Symbol.asyncIterator) && typeof value[Symbol.asyncIterator] === 'function';
+	export const asyncIterable = (value: any): value is AsyncIterableIterator<any> => !nullOrUndefined(Symbol.asyncIterator) && function_(value[Symbol.asyncIterator]);
 	export const generator = (value: any): value is Generator => iterable(value) && function_(value.next) && function_(value.throw);
 
 	export const nativePromise = (value: any): value is Promise<any> =>