public function shortcode_user_meta_date( $atts, $content = null ) {

    $atts = shortcode_atts( array('field' => ''), $atts );

    if(empty($atts['field']))
        return;

    if(!is_user_logged_in()) {
        return do_shortcode($content);
    }

    $user_data = get_userdata( get_current_user_id() );

    if( is_object($user_data) && property_exists( $user_data->data, $atts['field'] ) ) {

        $value = $user_data->data->{$atts['field']};

    } else {

        $value = get_user_meta( get_current_user_id(), $atts['field'], true );

    }

    if(empty($value)) {
        return do_shortcode($content);
    } else {

        if( is_numeric( $value ) ) {

            $value = date('F j, Y', $value);

        }

        return $value;

    }

}

add_shortcode( 'user_meta_date', 'shortcode_user_meta_date' );