Researchers studied whether eating dairy products at specific times of day could help people with type 2 diabetes manage their blood sugar better. Twenty-five people with diabetes tried two different eating plans for four weeks each: one that included dairy foods like milk and yogurt, and one without. The dairy plan included eating a high-protein breakfast and limiting carbs earlier in the day. Results showed that the dairy plan improved blood sugar control, reduced hunger, and activated genes that help regulate the body’s natural daily rhythms. This suggests that what we eat and when we eat it work together to help our bodies function better.

The Quick Take

  • What they studied: Whether eating dairy products combined with eating breakfast high in protein and limiting carbs early in the day helps people with type 2 diabetes control their blood sugar better than a similar diet without dairy
  • Who participated: Twenty-five adults with type 2 diabetes who were either taking diabetes medications or managing their condition through diet alone. The study took place in Israel.
  • Key finding: People who ate the dairy-rich diet had better blood sugar control (fasting glucose dropped by about 1.7 mmol/l), felt less hungry, and had less desire for sweets compared to when they ate the non-dairy diet. Their body’s internal clock genes also became more active in a healthy way.
  • What it means for you: If you have type 2 diabetes, including dairy products like milk, yogurt, and cheese in a structured eating plan—especially with a protein-rich breakfast—may help you manage your blood sugar and feel less hungry. However, this is a small study, so talk with your doctor before making major diet changes.

The Research Details

This was a crossover study, which means each person tried both eating plans. Nineteen participants completed both phases of the study. Each eating plan lasted four weeks, with a 3-4 week break between them to let their bodies reset. One plan included dairy products (milk, yogurt, cheese) as the main protein source, while the other plan had the same amount of calories and protein but from non-dairy sources. Both plans included eating a high-protein breakfast and limiting carbohydrates earlier in the day. Researchers measured blood sugar using continuous monitors that track glucose throughout the day, checked specific genes related to the body’s daily rhythm, and asked participants about their hunger and cravings.

This study design is useful because each person serves as their own comparison—researchers can see how the same person’s body responds to each diet. By measuring genes that control the body’s 24-hour rhythm, the study goes beyond just looking at blood sugar numbers and explores how food timing and type might affect deeper biological processes. This helps explain why the diet works, not just that it works.

The study was relatively small (25 people), which limits how much we can generalize the findings. The researchers and participants knew which diet they were following, which could influence results. However, the study was published in a respected diabetes journal, used objective measurements like continuous glucose monitors, and showed consistent improvements across multiple measures. The fact that 19 of 25 people completed both phases suggests the diet was tolerable.

What the Results Show

The dairy-enriched diet activated three important genes that control the body’s internal 24-hour clock: BMAL1 increased 1.8 times, REV-ERBα increased 2.2 times, and CRY1 increased 1.4 times. These changes suggest the body’s natural rhythm became stronger and more organized. Blood sugar control improved significantly: fasting blood sugar (measured before eating) dropped by about 1.7 mmol/l, and the overall glucose management indicator improved by 0.7%. People spent about 9% more time with their blood sugar in the healthy target range. Hunger scores decreased by 15-20%, and cravings for sweets also dropped by 15-20%. These improvements happened within the four-week period of eating the dairy-enriched diet.

The study found that the timing of eating—having a substantial breakfast and limiting carbs earlier in the day—appeared to work better when combined with dairy protein sources. The improvements in appetite control were particularly notable, suggesting that dairy may help people feel satisfied longer and have fewer cravings. The gene expression changes indicate that the body’s internal clock was functioning more efficiently, which could have broader health benefits beyond just blood sugar control.

Previous research has shown that meal timing and protein type both affect blood sugar control separately. This study suggests they work together synergistically—meaning the combination is more powerful than either change alone. The finding about circadian clock genes is newer; most previous studies focused only on blood sugar numbers without examining the biological mechanisms. This research supports growing evidence that when we eat matters as much as what we eat.

The study included only 25 people, and only 19 completed both phases, which is a small number for drawing broad conclusions. The researchers and participants knew which diet they were following, which could create bias. The study lasted only four weeks per diet phase, so we don’t know if benefits continue long-term or if people can stick with the diet over months or years. The study was conducted in Israel with a specific population, so results may differ in other groups. The study didn’t include a control group eating a standard diet, only compared two modified diets.

The Bottom Line

If you have type 2 diabetes, consider discussing with your doctor whether including dairy products (milk, yogurt, cheese) as your main protein source, combined with eating a substantial high-protein breakfast and limiting carbs earlier in the day, might help your blood sugar control. This approach appears promising based on this research, but larger, longer studies are needed. Confidence level: Moderate—the results are encouraging but based on a small study.

People with type 2 diabetes who want to improve their blood sugar control and reduce hunger should pay attention to this research. Those with dairy allergies or lactose intolerance should not force dairy consumption but could discuss alternative protein sources with their doctor. People taking insulin or certain diabetes medications should monitor their blood sugar closely if making diet changes, as their medication doses might need adjustment. This research is less relevant for people without diabetes, though the timing and protein concepts might have broader benefits.

Based on this study, you might expect to see improvements in blood sugar control within 2-4 weeks of starting this eating pattern. Hunger and cravings may decrease within the first 1-2 weeks. However, individual results vary, and it may take 8-12 weeks to see the full benefits and determine if this approach works well for you personally.

Want to Apply This Research?

  • Track fasting blood sugar readings each morning and note whether you ate dairy at breakfast. Also log hunger level (1-10 scale) and sweet cravings before and after meals to see if the dairy-rich breakfast reduces these throughout the day.
  • Set a reminder to eat a high-protein breakfast within 1-2 hours of waking that includes a dairy source (Greek yogurt, milk, cheese, or cottage cheese). Log this meal and your blood sugar reading 2 hours after eating to track improvements over weeks.
  • Over 4-8 weeks, track the percentage of time your blood sugar stays in your target range (if using a continuous glucose monitor), your average fasting glucose, and your hunger/craving scores. Compare weeks 1-2 to weeks 7-8 to see if the pattern improves. Share these trends with your healthcare provider at your next visit.

This research is promising but preliminary. The study included only 25 people and lasted four weeks, so larger, longer studies are needed to confirm these findings. If you have type 2 diabetes, do not change your diet or medications without consulting your doctor first. Blood sugar management is individual, and what works for one person may not work for another. If you take diabetes medications, dietary changes could affect how much medication you need, potentially causing dangerously low blood sugar. Always work with your healthcare team when making significant diet changes. This information is educational and should not replace professional medical advice.