diff --git a/doc/source/basics.rst b/doc/source/basics.rst
index e3b0915cd571d..917d2f2bb8b04 100644
--- a/doc/source/basics.rst
+++ b/doc/source/basics.rst
@@ -1726,6 +1726,28 @@ then the more *general* one will be used as the result of the operation.
    # conversion of dtypes
    df3.astype('float32').dtypes
 
+Convert a subset of columns to a specified type using :meth:`~DataFrame.astype`
+
+.. ipython:: python
+
+   dft = pd.DataFrame({'a': [1,2,3], 'b': [4,5,6], 'c': [7, 8, 9]})
+   dft[['a','b']] = dft[['a','b']].astype(np.uint8)
+   dft
+   dft.dtypes
+
+.. note::
+
+    When trying to convert a subset of columns to a specified type using :meth:`~DataFrame.astype`  and :meth:`~DataFrame.loc`, upcasting occurs.
+
+    :meth:`~DataFrame.loc` tries to fit in what we are assigning to the current dtypes, while ``[]`` will overwrite them taking the dtype from the right hand side. Therefore the following piece of code produces the unintended result.
+
+    .. ipython:: python
+
+       dft = pd.DataFrame({'a': [1,2,3], 'b': [4,5,6], 'c': [7, 8, 9]})
+       dft.loc[:, ['a', 'b']].astype(np.uint8).dtypes
+       dft.loc[:, ['a', 'b']] = dft.loc[:, ['a', 'b']].astype(np.uint8)
+       dft.dtypes
+
 object conversion
 ~~~~~~~~~~~~~~~~~