Figures for excess deaths from the Office for National Statistics (ONS) show around 1,000 more people than usual are dying each week from conditions other than the virus.
Reports said the Department of Health and Social Care (DHSC) had asked for the data to be checked, with a department spokeswoman saying circulatory diseases and diabetes “may be partly responsible” for the majority of excess deaths.
She told a national newspaper: “Analysis is ongoing. However, early investigation suggests circulatory diseases and diabetes may be partly responsible for the majority of excess deaths.
“The latest data highlights the importance of actively managing risks around heart issues as there is good evidence many of these deaths are potentially preventable.
“These statistics form part of the Office for Health Improvement and Disparities’ routine surveillance activities and are regularly discussed within the Department of Health and Social Care and amongst senior NHS leaders.”
It comes as the number of deaths involving Covid-19 registered each week in England and Wales fell for the first time since mid-June, in fresh confirmation the recent wave of the virus is receding.
But confirmed or suspected Covid deaths in Scotland rose in the week to Sunday. A total of 66 deaths were registered that mentioned Covid-19 on the death certificate in the week to August 14 in Scotland – an increase of six deaths from the previous week.
Covid-19 infections in the UK have meanwhile fallen to their lowest level for two months.
The number of patients in hospital with Covid-19 is also continuing to drop, though health experts warned infections were likely to rise again in the autumn and winter.
A new booster jab will be offered to everyone in the UK aged 50 and over from next month, as well as those with underlying health conditions, to increase protection ahead of future waves.
A total of 1.7 million people in private households are estimated to have had Covid-19 in the week to August 8, according to the Office for National Statistics (ONS).
This is a drop of 34 per cent from the previous estimate of 2.6 million for the week ending July 26.
Sarah Crofts, head of analytical outputs for the ONS Covid-19 infection survey, said: “Infections have continued to fall across much of the UK to levels last seen in mid-June.
“Our latest data show these decreases are among nearly all ages in England, with the lowest levels seen among children.
“We will continue to monitor the data closely to understand the impact of the summer holidays.”
The current wave has been driven by the Omicron BA.4 and BA.5 subvariants of the virus and saw weekly infections climb as high as 3.8 million in early July.
This was not as steep as the record 4.9 million infections at the peak of the Omicron BA.2 wave in late March, however.The latest estimate for people testing positive in Scotland is 164,100, or around one in 30, down from 260,800 in late July, or one in 20.