Nutritionist’s triple 30 rule aims gut health simply

UK nutritionist Dominique Ludwig says the “triple 30” rule—30 grams of protein at each meal, 30 grams of fiber each day, and at least 30 different plants each week—can make healthy eating feel less complicated while improving digestion, reducing inflammation,

A new nutrition rule is making waves in the UK for its simplicity—and for its promise that you don’t need to micromanage every bite to get results.

Dominique Ludwig, who has helped people eat healthfully for three decades, argues that most diet trends contradict each other and end up wasting “valuable time, money, and energy.” In an interview, she said: “In a world where nutrition is very confusing, it can actually be really simple.”

Ludwig’s approach is laid out in her new book, “No Nonsense Nutrition,” which she describes as a road map built around practical eating principles that work for both her and her clients.

At the center of it is her “triple 30” rule: 30 grams of protein at each meal, 30 grams of fiber each day, and at least 30 different plants in your diet each week.

She said that within four weeks of following the triple 30 rule. her clients can cut back on processed foods without feeling deprived or needing complex or strict plans. The shift. she said. often comes with reduced cravings and “food noise. ” better digestion. lower inflammation—which may translate into fewer aches and pains—better mood. and more energy.

“Sometimes you don’t need to jump down every rabbit hole. If you just start with the foundation, you suddenly see that food actually can be one of the most transformational things we can do to our health,” Ludwig said.

Protein at every meal, timed for fullness

Ludwig said people may already be getting enough protein, but that timing matters. “It stabilizes your blood sugars. It keeps you feeling fuller for longer,” she said. She added that getting protein in the morning is “really important” because breakfast can set the bar for the rest of the day.

Her recommendation is aiming for around 30 grams of protein at each meal using sources like Greek yogurt, fish, chicken, or legumes.

She emphasized that you don’t need to “eat heaps of chicken breast” to reach the goal—start with around 30 grams per meal. That typically works out to about 90 grams of protein per day, though she said some people may need more if they are larger or highly active.

She pointed to research suggesting adults benefit from around 1.5 grams of protein per kilogram of body weight (or 0.7 grams per pound) daily.

Ludwig also connected protein to longevity. She said getting the right amount is important for a long. healthy life and that as people get older they generally need more protein to prevent age-related loss of muscle tissue and promote a healthy metabolism. “Proteins are not only for our muscles, but they’re also for repair, they support our immune system, and our neurotransmitters. They’re really important,” she said.

Fiber is the ingredient she says gets overlooked

While protein draws attention, Ludwig said fiber is an underrated nutrient. “We’re living in this massive fiber gap at the moment,” she said. “It’s the missing link.”

According to her, fiber supports gut health, weight loss, and more by helping slow digestion, which she said can promote steadier blood sugar and energy levels. That can leave people feeling more satisfied after meals.

“Protein and fiber are like this dynamic duo; together they’re bulky, and that means they switch on all these satiety mechanisms,” Ludwig said.

Her target is 30 grams of fiber a day, slightly more than typical dietary advice. She based the recommendation on research from the American Gut Project, a study of more than 15,000 people led by the University of California San Diego, analyzing health and eating habits.

She also said high-fiber diets—rich in foods like beans, nuts, and whole grains—are linked to a lower risk of chronic illnesses such as heart disease and colorectal cancer, which is why she frames fiber as key for longevity.

Thirty different plants each week for microbiome diversity

The final part of Ludwig’s formula—30 plants in a week—is designed to widen the mix of nutrients available to the gut. She said the digestive system hosts colonies of beneficial bacteria, known as the microbiome, which she said plays a key role in health, from mood to energy levels.

To explain why variety matters, Ludwig compared the microbiome to a zoo. “Just as giraffes prefer different foods from lions, each type of gut microbe thrives on different micronutrients found in different plants.”

She said loading up on 30 plants a week is easier than many people think. Every little bit counts, from herbs and spices in the pantry to the plants in a morning coffee or tea.

She also advised not to ignore treats. “Don’t forget to treat yourself: fresh fruits, popcorn, and dark chocolate all help support a healthier gut in the long term.”

Ludwig’s examples of protein-and-fiber pairings include whole-grain bread and chicken or tuna salad, Greek yogurt with berries and nuts, or lentil soup with veggies.

The money-and-time question behind the rule

What ties the “triple 30” together is less about chasing perfection and more about having a foundation people can actually stick with. Ludwig’s pitch is that the rule helps people reduce processed food intake “without feeling deprived. ” and that it does so within a four-week window—while also aiming to improve digestion. inflammation. mood. energy. and cravings.

If diet advice has left people overwhelmed by competing rules, her message is blunt: start with protein at each meal, fiber every day, and plant variety across the week—then let the system do the work.

Dominique Ludwig triple 30 rule protein per meal fiber daily gut health microbiome processed foods longevity American Gut Project University of California San Diego