Try this:
DECLARE @tableHTML NVARCHAR(MAX);
SET @tableHTML =
N'<H3 style="font-family:verdana;color:darkblue;">Header1</H3>' +
N'<H5 style="font-family:verdana;color:darkblue;">SubHeader:</H5>' +
N'<H6 style="font-family:verdana;color:darkblue;">SubHeader2<br> SubHeader3</H6>' +
N'<table border="1";>' +
N'<tr>' +
N'<th style="text-align:right;">MiscColumn1</th>' +
N'<th style="text-align:right;">MiscColumn2</th>' +
N'<th style="text-align:right;">MiscColumn3</th>' +
N'<th style="text-align:right;">MiscColumn4</th>' +
N'<th style="text-align:right;">MiscColumn5</th>' +
CAST (
(SELECT
td = SE.MiscColumn1, '',
td = SE.MiscColumn2, '',
td = SE.MiscColumn3, '',
td = SE.MiscColumn4, '',
td = SE.MiscColumn5, ''
FROM database.dbo.table SE
FOR XML PATH('tr'), TYPE
) AS NVARCHAR(MAX)
) +
N'</table>';
EXEC msdb.dbo.sp_send_dbmail
@profile_name = 'Mail_Profile',
@recipients='******@email.com',
@copy_recipients = '',
@subject = 'Sending an email',
@body = @tableHTML,
@body_format = 'HTML';