The official eligibility criteria for IGNOU Master of Science in Dietetics and Food Service Management [M.Sc. (DFSM)]  is stated below:

B.Sc Home Science with specialization in Food and Nutrition, Dietetics and Clinical Nutrition
Or
PG Diploma in Dietetics and Public Health Nutrition or its equivalent
Or
Graduate (B.Sc. Hons.) or equivalent (MBBS, BHS etc.) from any of the following backgrounds: Home Science/ Food Science and Technology, Zoology, Microbiology, Biochemistry, Pharmaceutical along with the DNHE or CNCC or CFN offered by IGNOU. (Simultaneous admission for CFN/CNCC also permitted)

As you can see there are no mentions of Life sciences you aren't eligible for the course.

To get the official brochure for Master of Science in Dietetics and Food Service Management [M.Sc. (DFSM)] copy-paste the link below on your browser:

http://ignou.ac.in/upload/programme/MSCDFSM%20Prog.%20Guide.pdf

For the official eligibility criteria visit the link below:

http://www.ignou.ac.in/ignou/aboutignou/school/soce/programmes/detail/175/2

To know more about this visit the link below:

https://www.careers360.com/university/indira-gandhi-national-open-university-new-delhi/msc-dietetics-and-food-services-management-course

I hope my answer helps. All the very best for your future endeavors!

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