Persistent glomerular hyperfiltration is a characteristic feature of the early stages of kidney disease and represents a factor in the progression of chronic kidney disease (CKD). In this context, the benefit of low-protein diets (less than 0.8g/kg/day) has been demonstrated in slowing the progression of CKD, although the underlying pathophysiological mechanisms remain unclear.

Some studies suggest that the effects of protein on renal hemodynamics are primarily linked to the quality of the protein, particularly the amount of AGEs (Advanced Glycation End Products) consumed.

Recently, edible seaweeds have gained popularity in Western countries due to their anti-inflammatory, anti-diabetic, and antihypertensive properties. These seaweeds are also associated with the above-average longevity of certain Asian populations who consume them daily. Wakame seaweed (Undaria pinnatifida), which is locally harvested along the French Atlantic coast, has shown promising biological properties, notably antihypertensive and anti-diabetic effects. It has also been recently demonstrated that fucoxanthin, a compound found in high concentrations in wakame, possesses strong anti-AGE activity.

Dietary modifications are essential for nephroprotection, but they are often difficult to implement. This highlights the need to develop approaches that are both acceptable on a daily basis and sustainable in the long term for patients.

A Michelin-starred chef, known for regularly incorporating seaweed into his cuisine, is a sponsor of the project and has validated a set of adapted recipes that will be offered to participants to accompany the daily wakame supplementation.

The investigator's hypothesis is that a daily dose (5 grams of French wakame, dehydrated at low temperature and in flake form), equivalent to the average daily intake in Japan, could reduce circulating AGE levels in patients with stage III CKD. This would provide an additional protective effect when combined with the standard low-protein diet, helping to slow the progression of CKD over the long term.