how to reduce straining on toilet from constipation

Unfortunately, the damage done due to straining is only noticed late in life when various conditions emerge.

This is due to the fact that this damage is due to repetitive and progressive injury to muscles and possibly nerves passing through these muscles over a long time due to pressures generated by straining during the daily process of defecation.

A change in diet late in life does not lead to reversal of any major damage done.
A change in diet and lifestyle will help prevent constipation, heal existing haemorrhoids and prevent further recurrence, relieve some of the problems associated with Diverticulosis such as bleeding and infection. Further creation of bulging Diverticula may also be prevented.
Relief from Acid reflux due to a Hiatus Hernia may also be expected.

The structures that make up the human body are able to withstand great forces created by daily life but when unnatural behaviour that the human body was not made to withstand are adopted, the result is damage and suffering.