In the CDC infographic below, notice that a whopping 23% of South Asians have diabetes!

Source: CDC / Diabetes.

The CDC numbers above are corroborated by this research paper: Prevalence of Diabetes by Race and Ethnicity in the United States, 2011-2016 by Yilian J Cheng, Alka M Kanaya, Maria Rosario G Araneta, JAMA. 2019; 322(24): 2389-2398. Snippets from this paper:

What was the incidence of diabetes among various population groups in USA in 2011-2016 time frame?

(A) 12.1% among non-Hispanic white
(B) 20.4% among non-Hispanic black
(C) 22.1% among Hispanic
(D) 19.1% among non-Hispanic Asian

The Non-Hispanic Asian group is composed of several sub-groups. What is the incidence of diabetes among these sub-groups?

(D1) 14.0% for East Asian sub-group
(D2) 23.3% for South Asian sub-group (those of Indian sub-continent origin are part of this sub-group)
(D3) 22.4% for Southeast Asian sub-group

Observation: Look at the two lines in bold above. Incidence of diabetes is 12.1% among non-Hispanic white population but 23.3% among South Asian population — almost twice.

Diabetes Among Indian Americans has a good summary. An excerpt from this article about the MASALA Study from 2010:

In the MASALA Study the crude prevalence of diabetes among Asian Indians in California was 29% and prediabetes 37% which became 26% and 25% respectively when adjusted for the age (Table 103A). In this well-designed study, the prevalence of diabetes among Asian Indians was 400% higher than whites, 200% higher than Chinese, and 50% higher than blacks and Hispanics.

Asian Indians in the US enjoy a higher socioeconomic status (SES) than whites, which is a protective factor for diabetes in western societies. Ironically, adjusting for SES actually exaggerated the prevalence of diabetes among Asian Indians.

The diabetes prevalence rate in MASALA is higher than all other studies reported to-date but probably more accurate given the very robust protocol used.

MASALA Study: Kanaya AM, Wassel CL, Mathur D, et al. Prevalence and correlates of diabetes in South asian indians in the United States: findings from the metabolic syndrome and atherosclerosis in South asians living in America study and the multi-ethnic study of atherosclerosis, Metab Syndr Relat Disord. Apr 2010;8(2):157-164.

Source: Doctor's message to Asian Americans: Watch out for diabetes even if you're young and thin, LA Times, 2016.

For Asian Americans, the Screen at 23 Program was introduced in 2015. Multiple states like Hawaii (2016), California (2016), Massachusetts (2018), Illinois (2018) and Washington (2019) have adopted it.

Also see India-Specific BMI Cut-Offs for Obesity for some context.