diff --git a/src/groups/membership.js b/src/groups/membership.js
index e2b0bfc93a..7739445398 100644
--- a/src/groups/membership.js
+++ b/src/groups/membership.js
@@ -24,7 +24,7 @@ module.exports = function (Groups) {
 	};
 
 	Groups.isMember = async function (uid, groupName) {
-		if (!uid || !(parseInt(uid, 10) > 0) || !groupName) {
+		if (!uid || parseInt(uid, 10) <= 0 || !groupName) {
 			return false;
 		}
 
@@ -65,7 +65,7 @@ module.exports = function (Groups) {
 	};
 
 	Groups.isMemberOfGroups = async function (uid, groups) {
-		if (!uid || !(parseInt(uid, 10) > 0) || !groups.length) {
+		if (!uid || parseInt(uid, 10) <= 0 || !groups.length) {
 			return groups.map(groupName => groupName === 'guests');
 		}
 		const cachedData = {};